Sources close to the show tell TMZ ... the girls were all in a VIP suite at the Gulf Stream Race Track in Hallandale, FL last Saturday. We're told Nai Crooks -- who is Evelyn's assistant but used to work for Jennifer as well -- called out Jennifer ... who the other girls feel has become "too big for britches."

According to our sources, the two got face-to-face and Nai pushed Williams in the face to get her away. In the police report, Williams described it as being "intentional struck by Crooks with an open hand to the left side of her face."

Williams told police security from the production company then stepped in to intervene. Our sources say that's true ... but that security also grabbed Lozada to keep her from jumping in after Williams.

In the report, the officer states he saw no injuries on Williams and told her she could file a misdemeanor complaint with the state attorney's office if she wanted to pursue the matter further.