After Ida and about 18 inches of water in the basement, I’ve got all drywall off 2 feet off the ground and found there was no insulation behind the wall. Before drywalling back up I was thinking of either adding rigid foam (1.5 inch) between the studs or rock wool. 

Would one or the other make more sense? I would need to slide the insulation up from the 2 foot hole into the rest of the ~5 foot cavity. I don’t necessarily want to take more wall off right now.  

I can possibly see if a .25/,5 inch rigid board would fit behind the framing directly to the foundation wall, but not sure if there is room behind the studs. Assuming I’ll only be able to insulate between the stud cavity though.