From what I understood regarding Epic Publishing, Epic is completely funding the game, the salary for the devs, paying for the marketing etc. while the devs get's to keep the IP themselves. It's a risky move because with Sony, MS and Nintendo first party titles, those companies knows their devs, like Playground and Naughty Dog, they've grown with them and they know what Playground or Naughty Dog is capable of doing, they are like "family" in a sense (I know, odd word). What Epic is doing on the other hand is risking a lot of money on developer they might know know how skilled they are. Making a successfull game takes a lot of skill and Epic won't have that relationship with the devs they partner with under their publishing label.
In that regard I will actually give Epic some respect. What they are doing is risky and the games can easily fail, while the other companies like Sony with Insoniac or Naughty Dog, Sony know what they can do and has helped them grow over the years.