Well if he said if its anything like The Revenant, then not only the strong dark tone of the film but also the hard R rating is very possible, since I find it hard for them to land on a PG13 by bad luck. AVP was intentionally done PG13, but the producers here basically says "maybe, but we don't know lol". There is still hope for me.
As for the Predator's first journey there, yeah, uhhh, seems like the article's writer on that part as there is no quote to back that statement up. Not to mention that isn't said that Predators have been visiting Earth for at least the past 800 years? Someone over there in production gotta bring that up to their attention just to be sure.