They must have come from outside. We have stink bugs, which somehow get in house and are attracted to lights. Neem seems to work if used several times, allowing egg batches to hatch, between treatments. Now reading about HLVd. Doubt I have it since only have MD's cut of GG4. Thinking about bringing in 5 other cuts from seller, and wondering if I should just treat them as if they have it.I'm sorry you are having all this stress from these mites. Mites are a bitch once you get those bastards they are hard to get rid of. A mite-free garden is a happy garden. A garden with mites is a sad stressful garden. Smoking or vaping bug shit on your weed fucks up your high. Once you get mites you can have them for as long as you grow. I haven't had a mite in my garden in over 15 years.
Here's how I keep mites out of my garden.
1. I never take clones from anyone!
2. I never go into someone else's garden or let them come in mine.
3. I only clone my own seed-grown plants.
4. I keep the environment from getting too hot and dry. Mostly grow in cool-season only and shut down during hot summer for indoor grows., In hot Summer I grow outdoors. .