I have played at Thunderpick for 3 years, and i have nothing but good things to say. I would bet my left nut that they are not scammers(for the people who takes everything literally, relax, it's a joke).
OP, if your accusation is real, i don't think anyone here will be able to help you reach them, neither at casinoguru or askgamblers because they don't collaborate with any of those mediation sites. The only way you have to reach them is thru trustpilot, where they actually respond.
However i don't think this accusation is real. 0 proof provided, no screenshots of anything, just an "they closed my account lol". And then there's this:

Created account, wrote the post in 4 minutes, dipped, never came back.

God damn. OP clicked "post" and immediatly logged off. Bro has no time to waste. I wish i was efficient with my time as OP is with his. Impressive.