Randomly I happen to see PayPal mentioned in my Pro Sites settings, which is strange because I use Stripe.
Well I guess it defaults to PayPal when ALL PRO SITE SETTINGS ARE LOST. I haven't been changing the configuration, performing updates or anything. (I wasn't even messing with domain mapping, in case you see my other help request.)
I have already enabled Support Access. Please do not change any settings, but I could really use some WPMUDev support ASAP.