I feel your pain. I hope things are working out with the grow costs. I had a similar event. "Mr BigSh!t" (I use a slur here to keep perpetrator's identity a secret to prevent verbal warfare) pushed a Respect OG cut my way, claiming "BigSh!t" ultimate yield and marketability as far as OG's go. By week three, pure hermaphrodite. Upper colas were pistils, and lower nodes were stamens. First time I had encountered such a thing. "Mr BigSh!t" assured me that he grows out all of the strains he stocks. Again, "BullSh!t". Although Chem herm'd due to stress and not bad genetics, the end results are the same. Power companies have us by the "wallnuts". A single event can bring down the house!
From an operational perspective, I had to do something to prevent this king of "BigSh!t" in the future. I am now very reluctant to change any part of my system. If it is working, don't fix it. Seek out a marketable strain and cost effective nutrient system. Stick to it. Seek improvement in your flowering through small adjustments of controllable factors such as the distance your lights hang above your canopy, feeding schedule, light cycle(12/12, 13/11, 11/13, etc) and total days in bloom. Take good notes with every bloom and review occasionally.
I'm to preachy. Sorry. I understand your passion FunkySmoker. I played around with my soils early on. I experimented with formulating watering-only organic soil mixes(guanos, worm castings, etc) that would feed through bloom. I grew a cycle of Chemdog 4 that I acquired from the late Blue Sky Cafe in Oakland. My soil mix turned the lemony delight into a peppery nightmare. Tasted like sh!t. Couldn't give it away. Again, a single event can bring down the house!
For now, it is my opinion that you should not waste one minute of light time on those herms. Throw them away. Cut your losses now. Get a fresh bloom started ASAP. I may be misunderstanding, but those fem'd seeds may be of very poor genetic quality. Growing those seeds out could cause more of the same situation.
It can be risky to ask for advice. Nothing said here was meant to offend. You probably have already considered all of this. I do not consider myself an expert, just an enthusiastic cultivator.
Sincerely, good luck FunkySmoker.