Hugo, the Tower Master, eventually succeeded in persuading Annan.
If he had not wanted to imprison Salvatore in the Black Tower, but rather to let him gather strength and ascend to divinity...
Annan would have no reason to refuse such a good thing for Salvatore.
Although Salvatore would stay in the Black Tower temporarily after receiving the sacred fire, this was not forever... nor would he become a prisoner of the Black Tower, not destined to be locked within a Wizard's Tower for life like other Tower Masters.
With the blessing of the sacred fire, he would ultimately ascend to divinity.
And such a future was not far off... It would take at most three or four years, and Salvatore, free from the debuff of "chronic insomnia," would be able to assimilate what he had gained as a Gold Tier Transcendent.
With his cultivation, he would surely obtain the Book of Truth.
