Blaze in 06 is a semi-hallucinatory astral projection of Iblis that's "haunting" Silver and the question as to why she looks like a breakout-popular character from a handheld spinoff has a strictly Doylist answer. She's not "sealing" Iblis in her final scene so much as she's just taking the rest of her soul back and leaving. Otherwise how would she know "she would be accepted"?