But if moving masses can create moving "magnetic like" gravitational fields, then one could plausibly come up with some history of motion of conventional matter that could create the configuration of gravitational fields that we see in the bullet cluster. Can any such history result in the observed current configuration of conventional matter? I don't know.

Note well: I have only a BS in physics, and have not stayed in the field. Take all opinions with a train of salt. (Yes, I stole that typo from someone here on HN. Don't remember who, but it was worth doing deliberately.)