Maybe there are loopholes, but that's a slippery slope. If you set the precedent once, there will be Sophomores all over the NFL sitting out of camp because they didn't get a guaranteed endorsement/house/kickback.... The owners would never allow themselves to be pressured back into the same situation. ... and you know Jerry Jones would de everything he could to disallow it even if, in this particular case, it's the right thing to do.
Right now, no FO has to ever worry about a rookie or sophomore or even 3rd year player holding out. Yes, of course rookies can hold out, but probably for a few weeks of camp, not fractions of the season because the stakes are so much lower. I don't think anyone ever expects a Michael Crabtree scenario where his value was 0 for the first year because of a holdout.
Currently, rookies (right or wrong) have to trust they'll be paid for past and future performance on their second contract. I would guess, Paul Allen and the Seahawks might be more willing to do this than many other organizations.
... or we could all donate an extra $10,000 to bring him up to his earned 10 mil....