Tiffany, as I advised you - you are not a herp vet, neither are you set up to do your own fecal floats. Many diseases cannot be seen visually until the events are so severe it's often too late. Viruses and bacteria are not something you can ever see with the naked eye.
QT procedures are vitally important. Skipping them because you chose to bring in a snake when you didn't have room to QT it is your decision. However, we've seen people take this road before and we've read the posts as their snakes died slowly one by one or had to be euthanized. For me and for many experienced people here, skipping QT is just not worth the high price the snakes have to pay for this sort of shortcuts.
Your snake can in with mites? Then I have to assume you did not purchase him for a quality breeder. An even more vital reason for him to have been quarantined. Are you aware snake mites have a month long life/reproductive cycle? If the snake has only been with you 3 weeks he could very well still show another breakout of mites in the next week or so. Mites are an acknowledged vector for snake disease.
I hope you seriously consider what we are telling you about the safety and health of the snakes you keep.