It may not be technically unethical, but boy does Nick look like a real scumbag to me
Nick announced he was retaining Randazza and would be paying the retainer fee the next day. He also said he wouldn't be representing himself because he's not an idiot.
He later attempted to make contact David Weldon Schneider to ask for an extension.
Schneider ignored him. At least part of the reason for the lack of response was that Schneider was on vacation, but presumably part of it might be that Nick stated that he was retaining counsel, and it would be a potential ethics violation for Schneider to communicate with Nick if he believed him to be represented by Randazza.
Nick then filed that motion you mentioned, the same day that he turned up at Schneider's office to try to speak to him in person.
I don't know of the particular timing with respect to Nick's stream. If he directed profanities at Schneider before Randazza had been admitted
pro hac vice, that's even worse look than I thought.
Short of actual defamation Nick can call the opposing lawyer whatever the fuck he feels like on Locals. It's not in court and it's not in a filing. Nick may be a lawyer but he's still got free speech and if the Minnesota Lawyers Professional Responsibility Board disagrees with that fundamental premise they're going to have a long row to hoe when they try to enforce their unconstitutional rules in court.
The idea that ethics rules only apply to what is said in filings or in court isn't true. It's not hard to find examples of attorneys facing discipline for saying rude things in emails for example, even if the email communication is only between the attorneys and not directly involving the court.
What makes this different from the previous complaints that were summarily dismissed is that it involves a discussion on his show relating to his own practice of law (in this case, representing himself).
This is similar to the previous complaint in reaction to Nick's response to the dismissed ethics complaints from last year, where the comments on Nick's show involved the ethics complaints against him. I believe last month Nick said that the OLPR had not informed him if that investigation was still open. So we don't know if that has concluded yet, it may still be live.
If they thought his actions were definitely 1A protected, they can respond with a “determination that discipline is not warranted, without investigation", in which case no response is required. AFAIK, this is what happened with the previous waves of complaints, with the exception I already described above. If OLPR sends him a Notice of Investigation, however, he's required to respond within 14 days. Nick has confirmed he's filed a response to the complaint.
According to Rule 8(a), Rules on Lawyers Professional Responsibility, the threshold for an investigation is "a reasonable belief that professional misconduct may have occurred". That said, the majority of investigations do not result in any form of discipline.