I assumed he was indoor as I didn't see the word outdoor mentioned. You definitely run the risk of mold issues indoors 5 weeks into flowering. I'm not saying that sprays will always cause mold, but the risk is certainly there especially in the case of a novice. This is the newb forum if I'm not mistaken.
If you like Dutchmaster Reverse than by all means use it. Have you ever personally used it? If so what was your experience? I have used it along with a friend of mine, both cases I can say I saw little to no difference at all. Male flower production never stopped, didn't even slow down. There are a lot of other factors at play of course, in my case I'm nearly positive the herm was due to genetics. In which case I wouldn't really expect a product like reverse to work, and it didn't. That begs the questions why the herm popped up in the first place.
Dutch Master recommends the use of reverse 10 days or so into flowering as a preventative measure, or to use it at the first sign of trouble. 5 weeks into flowering again IMO is far too late for it to be effective. I've never tried it as a preventative. Then again the only herm I've ever had I'm nearly sure was due to genetics, in which case I don't see reverse helping. I guess if you tend to stress your babies then maybe reverse might help.
In any event, in this guys case I really don't see reverse helping the situation at all. Why spray the hell out of everything if odds are it won't help at all? I say get rid of the tranny.