Hi
I am also having the same ps4 online connection issue. I am trying to play with a friend as we have both just downloaded the definitive edition.
We have tried the various methods suggested in this thread over the past few days but no luck at all. Is there a proper fix in the works at all?

Otherwise I think we will have to try and get a refund on the game as we bought it for the co-op experience which is currently impossible.

Thanks for any help in advance