Fundraising Plugin – Money Directly to charity minus affiliate commission?

I would like to set up a website that promotes charities, and has links so that money / funds can go directly to a charity’s particular account (for security and trust reasons). However, I would also like to retain a commission (fee, or whatever you want to call it), say 5-10%.

Is this doable with this plugin now, or is the plugin customizable, or could this be a requested feature?

Also, can anyone think of this not being legal, say, in the USA, including California.

Also, any other feedback about this would be good. Does anyone know of any organization or website that does this now?

Feedback appreciated. Thanks.