Those little white bugs look like wood mites. I found some in Rei's substrate a couple weeks ago(I use repti-bark on top of coconut husk for aesthetics and humidity) and I got a fright too, but I checked Rei and found nothing on her and did some research and they're not harmful afaik, they're just wood mites.
I'm not worried about the little bugs like that as long as they are not a parasite to my snake.