Would a $10B prize accelerate development of a COVID19 vaccine?

No, it wouldn’t be worth it.

I have zero credibility to make this statement, but:

I feel like we might run into a Mythical Man Month dilemma if we toss TONS of money at it.

give me some up front and it will for sure.

considering the nobel prize is about $1 million and all due prestiges, im sure it would

From a layman's perspective: No not at all. Companies around the world are rushing full steam ahead to build one, you simply can't release medicines that quickly in the developed world.

They had multiple Zika vaccines completed within months of the outbreak years ago, most look incredibly promising and seem to work. Not a single one has been approved for clinical use yet and will likely be another year or two before it hits the market.