I'm just guessing that you couldn't use a crowd funding site to set up an escrow account to prove that there's a serious interest?
Edit: it sounds like these kind of sites insist you give out some sort of premium in exchance for any money donated. Even if people were 100% willing to pledge money just to be used in step #1 in the process [i.e., to show we are serious], and even if there was a way to say to a label, "here's some money, please go look for the masters and let us know if they are in a condition we could use", none of these sites would let you do that.
It would still be nice to read that these kind of ideas had been considered, and rejected for practical reasons. Or for there to be official word that we can stop dreaming, because there's no way to get this model to work as intended.