It looks like his play against Dallas earned Fox some extra snaps in the next 3 games.
Game 1: 23 snaps out of 72 plays (32% of the plays)
Game 2: 29 snaps out of 71 plays (41%)
Game 1: 23 snaps out of 62 plays (37%)
Game 1: 27 snaps out of 68 plays (40%)
So far it looks like Fox is subbing in for both Brockers and Donald at DE/DT (with Joseph-Day and Gaines covering NT).
Personally I wouldn't want to get Fox in the game if it meant taking more snaps away from Brock or AD ... but if Brock played a half dozen snaps at NT then Fox could pick up those snaps at DE. It would mean 6 fewer snaps for Joseph-Day/Gaines, but depending on game situations that might be OK.
AlbaNY_Ram