Advice please

[gobies et al]

I purchased 9 Trichogaster trichopterus 16 days ago and put in my 20 gal quarantine tank. At the LFS, I didn't see any spots, but under my lighting I could see spots on 1. I started tx with Jungle Ick Clear immediately, thinking it was Ick, and continued the treatment (including 25% water changes) for the next 3 days, by the 4th spots were worse, so did 50% change and switched medications to Quick Cure. At 7 days total into treatment, noticed yellow cast to skin and fine and larger spots, changed diagnosis to Oodinium; increased temperature to 82 and turned lights off. Over the next 5 days, 4 died and euthanized 2. It's been 4 days now, no deaths, skin appears clear, 1 still hanging out near surface.

Other inhabitants of the tank, 2 small Chaetostoma cf. thomsoni and 1 small Botia modesta (waiting to find more). The botia had been seen scratching, and the the other 2 partway up the glass but still hiding during this treatment.

Questions:

1) Should I just euthanize the lot of them? They were intended to go into my 300 (except the Chaetostoma cf. thomsoni).

2) Is colonization a real concern?

3) I hesitated to use CopperSafe with the plants and unsure of effect of adding another chemical into the mix. I have not had previous experience with Oodinium or using CopperSafe (have kept it on hand). What would the best route to have gone when became apparent not treating Ick?

4) I expect to continue quarantine at least 4 more weeks. Is there anything else I should be doing?

Thank you for any help you can give me.

[Qattarra]

I'm not very experienced here, I would do a couple water changes until you pretty much have changed 100% of the medicated water. I would keep it warm and dark. I would also add salt and aeration to help ease the fishes stress. I think a couple days in very clean water might help. It would also be helpful to see a few clear pictures of the infected fish. If you can't take a picture, look it up on line and just let us know if it looks something like or similar to, and what is different. No one wants to see you lose any fish , we'd all would like to help. Fish diseases are difficult to ID properly and know how to treat it. I hope someone here might recognize the problem and know how to treat it. My heart goes out to you and I'd like to see you save your friends.