The accusations of the account being fake didn't arise until the screenshots were spread on twitter then kiwi farms and the account itself was only deleted when Nick took out his phone to "check something" regarding the accusations.
Hmmm, you seem to be having some trouble here, so I'll state things plainly:
The burden of proof lies on the account holder to establish that he is in fact Nicholas J. Fuentes. This is of course beyond dispute and just the ordinary way of establishing a basis of facts. One does not simply prove a negative, nor is one required to. Those who make the claim have to prove the fact.
So let's look at the facts:
1. On May 25, 2022, an account on Twitter appears named MrKrabs9000.
2. This account displays a similar manner of posting like previous accounts that have been used by Nick Fuentes, namely:
A. The use of a Spongebob-related iconography for the account handle and profile picture
B. Common phrases used by Nick Fuentes on prior Twitter accounts. For example: "hey"; "imagine eating this good."
C. Following some accounts that Nick followed on his previous accounts.
D. Discussing Cozy viewership numbers and Google trends
3. This account was retweeted and rapidly gained followers, many of whom were Groypers.
4. The account was allegedly deleted when Nick took out his phone on his show last night, after someone asked about MrKrabs9000 is the superchats
This represents the totality of circumstantial evidence that might lead one to believe MrKrabs9000 is Nick Fuentes. But this is merely circumstantial. This is not conclusive evidence because Nick Fuentes himself has not declared that he is the owner of the account MrKrabs9000. And here lies the problem. Nick Fuentes has not claimed ownership of MrKrabs9000.
Here are facts we know about prior Twitter accounts operated by Nick
1. Nick establishes ownership by stating his new account on Instagram/Telegram/Twitter group chats.

Here Nick notifies the group chat of his then new Twitter account, chumbucket5000. As of May 26, 2022, there have been 0 messages from Nick Fuentes claiming ownership of the account MrKrabs9000, thereby running counter to established behavior.
2. Nick follows the same people on each subsequent new account. This includes people like Ethan Ralph, Bryson Gray, TTG, Biker Bandito, redpilledjacob, Sewer Lizard. Interestingly, MrKrabs9000 followed accounts that Nick Fuentes doesn't follow, like Louis Groyper, Soulja Boy, and NJF defender, while refusing to follow people like Sewer Lizard.
3. Nick does a Twitter Space on each new Twitter account. This has been the case for farmerkiller, chumbucket5000 and krabbypatty5000. MrKrabs9000 did not do a Twitter space, which further raises doubts as to the authenticity of this account and why this was not done.
4. Nick uses a unique header image for each account, typically something representing a liminal space. MrKrabs9000 did not have a header photo.
In light of this, let's review the circumstantial evidence that Nick is MrKrabs9000:
1. MrKrabs9000 is created on Twitter. Nick has not claimed ownership of this account on group chats, nor has evidence appeared suggesting otherwise. Some might claim that it is in Nick's interest to deny ownership of that account because he uploaded a clip containing gay porn. But this thesis gets the timeline of events wrong. Nick would first have to establish that he is the owner of that account. If said account goes on to upload a clip containing gay porn, that would be conclusive evidence and an embarrassment for his movement. If the first step has not been performed, namely authenticating the Twitter account, then all tweets made would be the work of an imposter.
2. This account does not indicate a similar manner of posting upon close examination
A. Nick uses Spongebob-related iconography for his profile picture and handle. He does NOT use a Spongebob character. Mr. Krabs is a character in the TV show Spongebob Squarepants. Previous accounts were not named Spongebob9000, Patrick9000, Doodlebob9000, etc. They instead used artifacts from the show like Bran Flakes, Chum Bucket, krabby Patties, etc.
B. The phrases used on this account are inconsistent with Nick's posting style. For example, MrKrabs9000 posted a picture of a pizza pie and glass of Pepsi, with the caption "imagine eating this good." Nick has not been posting pictures of the food he eats on his new Twitter accounts. Moreover, this particular meal was posted on Nick's Instagram 1 hour earlier, so it was not an original photo. This further raises doubts as to whether Nick owns MrKrabs9000 because we don't see any original images or content.
C. MrKrabs9000 did not follow accounts like Sewer Lizard, while following accounts like Louis Groyper and NJF Defender.
D. Nick posts screenshots of SimilarWeb statistics on his Telegram channel. He has rarely shown Google Trends, except on commentary streams. Furthermore, Nick has never uploaded a screen recording of his phone showing these statistics. This is a pattern of behavior inconsistent with what we know about Nick. The statistics he shows to the public can be accessed by anyone, not just Nick. Nick has never shown gay porn on stream, and it further establishes an inconsistent pattern of behavior, appearing at the same time as a suspect screen recording.
3. Several Groypers have admitted that they mistakenly believed MrKrabs9000 was Nick. Louis Groyper, the account followed by MrKrabs9000 but not Nick, admitted as much. He also had several Groypers in his mentions upset that he was retweeting a fake account claiming to be Nick. Michael Alberto, the YouTuber and Cozy streamer, also admitted to making the same mistake, stating that he was not in any of the group chats where Nick links new accounts. That's why he was unable to verify it. This account rapidly gained popularity because of Groypers like these, leading to a snowball effect where others believe MrKrabs9000 was Nick. Interestingly, this account was unusually retweeted by people that hate Nick and America First. It raises questions about why these people in particular were trying to raise awareness of this account

Dalton Clodfelter, a Cozy streamer and Groyper general confirmed that MrKrabs9000 was not Nick Fuentes on his now suspended Twitter account, Fakecel123.
4. No evidence has emerged conclusively linking the moment Nick took out his phone to the moment MrKrabs9000 was deleted. The timestamps need to be matched down to the second, and this has not been done. Furthermore, it is plausible that the person running MrKrabs9000 was waiting for Nick to check Twitter on stream before deleting it. So this also cannot serve as evidence that MrKrabs9000 is Nick.
The burden of proof lies on MrKrabs9000 to prove that he is Nick. He has not done so, so the task was left to bad actors attempting to verify through circumstantial evidence. A review of this evidence shows that it has not been established that MrKrabs9000 is Nick Fuentes beyond reasonable doubt. Given that there are parties that have been attacking the America First movement on KiwiFarms, on Twitter, and on Discord, we can conclude this account is likely the project of one of these groups.