California  |  Sexual Harassment

I am a landlord of a multi-tenant building. I pay a security company who sub-contracts to other security guards. I received a complaint today from one of the tenants, that his employee/girlfriend was requested to have sex by one of these security guards. The tenant was upset and wanted repercussions. What can be done legally if I wanted to keep the guard? That employee/girlfriend might be lying because for months, we have caught her soliciting catalogs and selling goods for her own benefit, violating the boyfriend's lease. That security guard has repeatedly told her that she was not allowed to pass out catalogs to customers and other tenants and other tenants' employees. We believe that since we recently warned her to stop soliciting, that she may be trying to deflect that blame and make us worry about a sexual harassment case. What do you recommend to do with the security guard/company? What should we do to get that employee/girlfriend of the tenant to stop soliciting goods? On video surveillance, the catalogs look almost like magazines only.