Considering that the way reviewers birds are raised is an unknown, I would not even consider their complaints in my considerations for a hatchery. They aren't worth noting. You're going to be hard pressed finding a breeder or hatchery that tests for LL as it's not required so I suppose flocks...
Hatcheries are required to have regular testing for disease to keep their npip required to shop birds.
Npip would shut down the hatchery if the birds had LL, where'd you hear this? It sounds like hogwash.