Room above garage – Insulation redo after “Retrofoam” fumes – GreenBuildingAdvisor

We recently had a room above our garage insulated with “retrofoam” or “injection foam” and based on the SDS provided, it was supposed to be a non-off gassing type of product. Well, that wasn’t true, and the smell has been strong in there with VOC levels being picked up to be 1500+PPB on the airthings monitor since the install. 

After some back and forth, the spray installers are willing to remove all drywall and insulation from that room on walls where foam was injected.

I plan to redo the insulation in this room using Rockwool R23 in the 2×6 stud bays (24OC).

Q1: Do I need something like a vapor membrane on top of the OSB before drywall? (Zip 18914  – Chalfont PA – Zone 4a?)

I also plan on using a bead of spray foam at all locations where the stud meets the OSB in each bay as marked in red in the image. Builder had sprayed the OSB joints before installing the kraft faced R19 insulation. 

Q2: Will that bead of spray foam help at all?

During the home build stage, I took pictures from inside the garage and noticed that there is bare OSB facing outward into this “attic” zone, on each side of this room.

Q3: Do I need to add anything to this bare OSB on the other side of this wall, shown outlined in red?

I noticed that there is some sort of barrier on the wall shared with the closet. Indicated this in the image taken from inside the room for reference. 

Any other recommendations to help me correctly re-insulate this room and help bring the temperatures to a more stable range?