5 years post RAI. Should he still see an endocrinologist?

Those post RAI or thyroidectomy, do you see a primary care provider or an endocrinologist for hormonal management.

My husbands primary doctor says he can manage his synthroid post RAI. He’s had numerous dosage changes and some mental health changes occur exacerbated by hormonal fluctuations. We’ve relocated and he doesn’t yet have a local endo.

I’m of the thought he should be seeing a specialist still but wanted to get some outside insight first.