Sorry for your problems.
I do wonder how you determined the success rate for Ich Attack... I hope you are correct, I only know several people who failed with it and none who succeeded.
The other thing which is not helping is your temperature setting. 81F is sufficiently high to make Ick more virulent but not high enough to kill it. You need to go to at least 86F, and ensure that you have some effective medication in the tank as you raise the temperature, and also ensure that you have very good aeration, otherwise some fish may suffocate. (In your case, danios most likely will suffer most).
If you intend to continue with Ick Attack, bring temperature lower. Quinine works on Ich Parasite in all of its phases, and Ick is less aggressive at lower temperature. Chances of this curing Ick are still not good.
If you want to solve the problem, get one of the medications that is effective against Ick. These include Ick Guard Crystal form (Mal Green+Acriflavine+Salt), QuickCure (Mal Green+Formalin), RidIch+ (ditto). All of these meds work better at higher temp, but don't raise until you dosed. My personal preference is Ick Guard since Formalin is toxic and not a must... but any of the mentioned meds should work.
Also, judging by your words, you have lots of Ick in the water column right now... a very large water change before treating should help.
Good luck!