I feel like we shouldn't miss the point here: you can't impersonate me and take donations in my name without my consent, no matter the currency (or regulations or whatever) being used. Make it opt-in, not "opted in by default and no way to opt out".
I suggest you pull your site before this PR gets even further out of hand, then reboot. If you continue to pursue your project, partner with a couple projects that opt-in (free publicity for you both) and work to their needs. Once you have things in order, then you can think about something more automated.