Not even assuming GP would. In fact, I would assume that even if BL had stopped or let go of her throat, GP still probably would not have charged him.
IMHO the bodycam footage indicates that GP was an extremely passive person who was unlikely to blame BL for anything which is common in DV.
As someone who has experienced DV I agree, it's very under reported. Where I live, as soon as LE are involved, the option to press charges is out of the hands of the victim. The only way out at that point is if the victim says they were lying which can in turn, result in charges against the DV victim.
BL must have been quite vicious and done quite a bit of damage. Maybe the kind where he had no choice but to continue pressing on her? Either that or risk GP charging him with attempted murder.
it might have gone quickly. this says could take as little as 60 seconds:
Signs of Strangulation | Critical Analysis RN Consulting
ugly. let us hope that GP was quickly unconscious.