Well they are either scorched, dried out, or have been got by something. I think that as you dont know what it is, get the good bud down early than later.

its either something inside the plant or something about the environment. So to answer your question , imho, get the environment sorted before you considered bud rot stuff, because your starting from a worse case and people have had mixed results with it. Your R.H during flower is too high and it encourages bud root, so you might want to look at it, I dont have any idea of implications of the air may contribute. in terms of what it may bring in. Considered a grow tent in your room ?