So it sounds like this was DMCA abuse by Funko, aided and abetted by BrandShield, and it resulted in damages to you. Also sounds like iwantmyname just went along with it, they are probably conditioned to do so by the rules.

I would write up a complaint and send it to the incoming FTC Commissioner. Yes, I'm serious. From the signals Trump is sending if there is ever a time when Republicans may support some form of DMCA reform, it's now. He's on record talking about punishing Big Tech and supporting "Little Tech." You're Little Tech. Send copies of your letter to Funko and BrandShield. Also reach out or at least send a copy to Matt Stoller, the guy who publishes a very popular newsletter about monopoly, anti-trust and corporate abuse in America, he will be interested. Go for the throat.