Yeah - concur with JayT - capsaicin is oil soluable. Alcohol too, so it's a wonder Scovie can ever taste anything fiery, but that's a discussion for another day.
I think you need to let the chicken soak in the powders/hot sauce for a while - like 6-8 hours. enough time to really get it soaked in, so that when the fry oil hits it, it's not stripping away the capsaicin.
That said, you're unlikely to get much of a burn from the cheetos at that point regardless, since they're on the outside. Could get a nice crunch from 'em though.