That said, I would not be surprised if none exist. The more payment processors you support, the harder it is to avoid handling the money directly, which means more legal hurdles (regulations, liability); the simpler alternative (that snowdrift.coop is currently pursuing, for those practical reasons, although it is limiting in some respects) is to coordinate donations though other platforms.
[1]: Aside, I was trying to write this sentence in the form "re-review the information for [up-to-date-ness]", but couldn't think of the right word. "Accuracy" is close, but doesn't capture the element of time. Any ideas?