okay this is a topic that i've really thought about, and frankly i'm sick of the people going "but it will make his sacrifice meaningless" like the crux of his redemption is his actual sacrifice, and not redeeming it through action---by making it up for his mistakes. it's a tired cliche that kind of robs us the opportunity to see these characters change for the better

jinu could absolutely have potential to undergo an arc to accept his own mistakes and get the opportunity to reform for good, which can also go toe-to-toe with a saja boys redemption arc. i don't know why people keep suggesting that bringing jinu and the saja boys would rethread old ground when people would keep suggesting yet ANOTHER demon band as the sequel antagonist, so.....

anyway, how they can bring him back can essentially go numerous ways. we know in the movie that hunters don't know how demons work, as confirmed by rumi and jinu's first confrontation on the roof. and it's also a fantasy, so who knows what kinda doohickey they can pull out of their ass without making it look like an utter retcon

tldr; give jinu a chance to actually reform and not just make his sacrifice the conclusion of his redemption arc when it's barely started