I've seen Follow Me redirect moves in Max Raid battles, but the moves used were the regular moves, not D/G-max moves. So can they be redirected?
Yes, they can be. I’ve seen it a few times in VGC, when it was pretty obvious that the move was supposed to hit the other Pokémon. For more evidence, I read this, and it also says the Gmax/Max moves will be redirected. Unless it’s a HA Duraludon or a HA Barraskewda, of course (Stalwart and Propeller Tail).
Hope this helps! :)