Hatcheries in all 50 states have to be tested for PT and be clean of it in order to legally sell hatching eggs or birds of any age.It's a small local hatchery that I wouldn't feel comfortable naming as it's only a supposition. If it turns out to be something that could of originated with them then I will definitely name them and contact them. I did contact them at the time and they replied that they hadn't had any issues being reported by anyone else. So maybe just a coincidence? I can call the lab in the morning to possibly get an early opinion. Hopefully know something then, although I know it takes a week or so to get all results.
If they are a "real" hatchery you shouldn't have a worry in the world about your chicks having PT.
If it is a "backyard breeder"...different story, but I still doubt that it is the problem.