TRT lowers cortisol, not good if you have an adrenal insufficiency. Secondary hypogonadism can present with low testosterone and low cortisol.
HCG which mimics the pituitary hormone LH, which increases testosterone and increases cortisol as well as other hormones.
You likely don’t have an adrenal problem, but rather a pituitary signaling hormone insufficiency.
I wouldn’t expect your Endo to be very helpful helping you dialing in on TRT, as Endo’s the majority of their time are clueless dishing out protocols that result in treatment failure.
So you’ll need to be your own advocate. Avoid protocols with injections every two weeks, at a minimum you want to be injecting 80-100 mg once a week wait a minimum of six weeks for lab testing. Twice a week is common, so 40 mg twice weekly.