Then it would seem to come down to this section:

"Tennessee county health departments follow Tennessee law and provide medical treatment and vaccinations to patients as young as 14 without parental consent if the individual provider determines that the patient meets the definition of a “mature minor” in accordance with Tennessee law."

and what normally constitutes a healthcare professional making that evaluation. If it normally takes that kid's family doctor/PA who has a long standing relationship, access to medical history, etc, then changing from that standard is challenging.

Stepping outside of precedents is hard and risky.