I had a similar issue and ended up using https://www.antom.com/ to fix it. Their setup made it easier to manage different payment options without having to build anything crazy on my own. Might be worth checking out if you're still stuck.
I see it's been a while since you’ve posted, but I just wanted to ask if there's been any update on this or if more payment methods have been added since then? I'm in a similar spot where the current options aren’t a great fit, so I’d love to...