Maybe that was the rumor for Dreadnought? I remember that they were looking for a monetization expert or something.
Edit:
Here you go
http://www.gamespot.com/articles/spec-ops-the-line-dev-working-on-free-to-play-game/1100-6416537/
Yeah, that's for Dreadnought.
I'd be very surprised if Dead Island 2 was F2P but it is possible.
No way it is.
You wouldn't have a F2P game up for pre-order. Nor would you have a spin off F2P game and a $40 spin off, if you'd just make Dead Island 2 F2P.