It's an Indie game just a rough first pass is enough for their needs so the contractors could just be fivers for all we know.
What it doesn't add up is the PS4 dev kit cost unless Sony did give it to them.
Very low operating budget and just because you can do a cool demo in 48hrs it doesn't mean you can actually make a game out of it in a short time as well.
I think it's a lot of delusional participants that got caught up because the media hyped the demo.
At the end of the day it's just that, a demo and they are all over their heads.