AFAIK it goes to both. However as far as I understand the whole situation the Devs get a massive payout if the game reaches a set number of purchases during early access. The amount is so high that the publisher fears that publishing the game is going to be a net negative for them (the publisher). This is why the publisher has tried everything legal and supposedly illegal to get out of paying this bonus.

So in short: The money goes to both but if you want to screw the publisher buy it during early access.