It's somehow revealed that Newt, like Credence has been abused and degraded his whole life and recognised the signs in Credence and was able to get his trust and help him.

Credence recognises Newt's abuse too, and want to help his friend like Newt helped him. Newt insists it's 'long over' but Credence knows from Newt's scars, pain like that doesn't go away without help.

Graves, Tina, Queenie and Jacob step up and everything changes

N.B. abuse can be family, Hogwarts-related, domestic but it was long term physical abuse (can include mental/sexual) similar to Credence