Unless you can show that he actually mislead users for financial gain I don't think you're going to get authorities involved.
Weirdly, they announced they would no longer accept BTC (on grounds known for years) right after they dumped.
I have no idea if he dumped his Bitcoin before announcing the change at Tesla, but misleading a bunch of people while leaving himself a technicality escape hatch would be extremely on brand for him.
Musk claims that Telsa never sold any of their bitcoins before the price collapsed when he reversed course on BTC, but who the hell really knows at this point?
Either way, he has certainly gained financially from boosting Tesla's stock, which lying about crypto is part of...
This was very easy to find, and makes me question your position that you weren't aware of it.