Great! Keep up the good work.
Might I suggest that since he is in a one gallon, you get a liquid medicine that has indications for drops/gallon, because otherwise it will be hard to measure out. I find that most things asking for 1 tsp/10 gallons equals about 8 drops/gallon, but I've not done this with meds.
It might also be advisable to pick up some stress coat for him, as fungus usually growns as the result of an injury on the fish's body or a scraping on the slime coat. Netting can be very traumatic to bettas, who have sensitive skin, so perhaps you could scoop him up gently in a cup in the future? (You'll want this cup to have a lid so he doesn't hop out) It would also be a good idea if you continue to use nets to have a net for each fish as they can spread diseases to one another very readily.
If he isn't eating, perhaps you could tempt him with live food? I've found that with conditions on the face and gills, the fish become very reluctant to eat, possible because their faces are sore. Sometimes live food will do the trick, but if not, they can go several days without eating. If this is the case with your guys, perhaps once he starts eating again, you could give him something a little richer (blood worms, etc.) to give him good nutrition following recovery so he is at his strongest to heal. When my bettas are sick, I do 4 pellets in the AM and 2 blood worms in the PM, though my fish are in 5 gallon heated, filtered tanks, so they have higher energy needs.
Hopefully your little fishy feels better soon! I find fungus to be much easier to treat than bacteria for whatever reason. Perhaps because it is superficially occuring on the skin, rather than something that has to get all the way into the fish's body to be treated.