The trouble is that he'd need to find sympathetic legal counsel in these juristictions to act pro bono, as launching three lawsuits across three countries isn't cheap.
He doesn't have to sue in Europe, just sue in the US on the basis of forum contact with an American website or because part of the criminal conspiracy to DDoS occured in the US with US actors (Liz & Co) and then take the verdict to Europe to be reinforced there. Under IPL/conflict law treaties EU courts have to honour a US verdict, especially when the case is urgent (imminent threat to DDoS). Again, not a lawyer and this does not constitute legal advice, but US verdicts are routinely reinforced in EU courts.
all dos attacks are illegal but glowies can't do anything about them.
Actually yes they can and they do.
Interpol does prosecute DDoS in cooperation with international partners.
what are the glowies supposed to do about it?
See above. The myth that you can't get caught for DDoSing is a lie spread by cyber criminals to get people onboard with their DDoSing campaigns.
keffals admitted to it, thats why i mentioned the scotland yard. normies wouldn't ddos kiwifarms without keffals, so he is responsible
It's not just Keffals' public tweets. We have rims and rims of evidence from their public Twatter accounts where they were openly stating they were DDoSing, openly blackmailing Joshua Moon's internet service providers,
tweeting 48 ultimatums at them to blackmail them into compliance, lest they be added to their DDoS list. There's also the actual DDoS list on the GrayHat Academy account on Github, with Liz and Kevin both being listed contributors with code commits in the public log. All this is evidence of criminal conspiracy to DDoS KF & associated internet service providers.
Then there are the threats to attack the Tor network itself (which is used by dissidents and military and is used in combat zones even) ...
p0wning the wrong Tor node just to get KF...

Open public threats to murder Joshua Moon...

The evidence of a criminal conspiracy is voluminous.
Always remember:
if they could take down KF legally, they would've done so years ago.
They are resorting to cyber crimes like DDoS because they can't and won't use the law.
TRAs actually hate LE, they think they're above the law.
In fact, Keffals' fellow TRAs who are even more far-left and ACAB than he is, they now think he's getting too chummy with the cops:

And yeah, I know he said "Don't look at Twatter", but fuck, they are doing it all out in the open. He also said: "Keep archiving no matter what", so...