Prior to discharge was a new CT done to verify the bleeding was stopped?
However, I agree , he needs to return to hospital for followup for increasing symptoms, and new imaging for possible rebleed since a possible change of pain "all over his head" are occurring.
New symptoms > new tests........always the expectations ...demand them.
If he doesn't want to go to ER, have your PCP order them, but get them done. And wait for what they call a Wet-read - so the radiologist can call the PCP for a preliminary reading and if something is found, your doc can arrange for a Direct Admission to the Hospital. And that way they can give you an immediate copy of the films to carry with you.
You already know there is boney problems (the original CT showed that with the skull fracture) , so also ask for an MRI, it can help find finer problems.
What else can you tell us?
Big guy or not, TBI's knock down anyone, ask any pro-sports player.
Best wishes.