Dying fiddle leaf fig

[Lola]

Help! I made an account specifically because I don’t know what else to do! I have a beautiful 8ft tall fiddle leaf fig. I got him at about 2 ft tall three years ago and he’s been growing amazingly! I recently repotted him and he seemed to be doing fine, but then a few weeks later I noticed he had spider mites. I treated it with neem oil, dish soap and some alcohol mixed together in a bottle with water which I read on another forum works well for spider mites. Since then he’s been going downhill. He started dropping leaves like crazy, they would turn yellow which I thought might have been from the alcohol? But then some started turning brown and the leaf stems are soft. I suspected root rot but I checked the roots and they aren’t brown or mushy and look fine. I’ve attached some pictures of the most recent leaves to come off and my FLF (he’s so bare now!!) I purchased some root supplement and am misting him frequently, as well there is a humidifier right beside him. I’m at a loss as to what is wrong and what do to. I really hope it’s not too late.