The 2 heavies after Dollar Bill

Referring to Saint Louis and the guy Reggie (Ice Cube) was working for.

Whenever I rewatch ... I miss some scenes, but assuming Reggie and his buddy were trying to get back money owed. But was that the case? Also who was the guy that hired them & showed up near end (i.e. was with Reggie when they grabbed him and put him in trunk)?

Now I would assume Louis wasn't trying to get money back or yet he wouldn't have destroyed the establishment that was bringing in the bills. So was it stated his issue with Dollar bill?

Thanks ahead to anyone with good answer.