TN should have a veterinary board that you can report this to.
Their license could be taken away.
It is not normal for a place to have that many problems reported by their clients. Techs can administer anesthesia under the supervision of a vet but I'm not sure if they have to be licensed in TN to do so. I have never heard of a tech doing a neuter and my guess is that it is illegal.
Maybe try the number at the bottom of this page:
Tennessee Department of Health: Board of Veterinary Medical Examiners