Pegula's SHOULD pay for most of the new stadium...
With that said, look no further from the New York Power Authority - a literal cash cow in our backyard taking in a TON of money. They helped with the build out of Canal Side and they should help secure the future of the Buffalo Bills in our own backyard.
I would even advocate that the Public Bridge Authority should throw in some funds from that cash cow, too.
I also bet you will see other private developers (aka Delaware North who alluded they were conflicted buying the Bills but would be interested in a partnership with a new stadium.)
It's going to take a creative public-private investment to make a reno or new build work.