I am assuming Grimes stays out for game 5. RJ, Hart, and Deuce can pick up slack there with no worries. I would also sit Julius so he gets a bit more time to get right, 5 days if we need him in game six, more if we win and wait for the next round.
That would mean Mitch Obi RJ Hart Brunson start with Hartenstein McBride and Quickley as the main subs with the possibility of seeing DeQuan Jefferies as the only other strong body to pull off the bench as a sub forward. I think that is a better choice than trying to play Fournier as a later day Steve Novak though that seems more like the direction Thibs decides to go.