If I recall correctly from the last time they ran this quest, you only got them during the quest. So they were like items you got on the path that allowed you to use the prefights. Basically to stop Steve from becoming a god except in the one specific quest he was allowed to. But to be fair I haven't done any of this one yet so may be incorrect.
Pre-fight is only available in Knull's Void.
I think they get unlocked as you progress iirc
OP is not talking about the persistent charges. As you rank up, more of Steve’s pre-fight abilities appear. OP already had him ranked up all the way but only has the initial two abilities. I am in the same boat.