Sorry to hear your problem. I learned the hard way about qting new reptiles. So now it is a strict 90 day minimum qt for any reptile coming into the house! I have a rack in the living room and for the newby. They never make it past the living room until that 90 day mark and if i discover any issues its 90 days from the time I think it is curred before it makes its way into the reptile room. as for mites i've only had one battle with them but it worked in 7 or 8 days. 2x a day soaked in warm betadine solution the color of weak tea, pick off and dispose of lose mites with a qtip. house all infected animals in glass or plastic with only paper towels for substrate and only decor should be a plastic hide and a plastic or glass water dish. be sure to sterlize and switch out the hide and water containers with each soak of the animal and thourghly clean the enclosure. with a rack system you may as well treat them all this way or it very well could turn into a vicious cycle. mites are like roaches if you dont get every last one and the eggs you wont get rid of them for good. I also think I would let the breeder know that your new addition has mites. Don't be rude because it maynot have came from him. You can get them from bedding or if you havent properly cured decorations that you brought in from outside etc. but a warning to be on the look out to the breeder wouldnt be a bad idea imo.
Good luck