He definitely shouldn't do shows like if it was the last time.
He could get nodules or whatever within a few days, months or years if he did that.
Risking other kind of vocal problems such as bowing as example too.
His voice could get even deeper making it harder to perform his older songs.

He should sometimes do speeches before long Dry County solo and maybe even shout it out sometimes (but not scream or yell it like if it's 1995 or 96.)

Vocal damage happens easier than you might think.

Be careful about what you wish for.