You can ask him to leave for part of the exam, call her at home and ask her about your concerns, continue to document his and her behaviors.
By doing that you have expressed your concern for her, and let her know there is someone outside the family that is available to talk to- someone who knows the resources available.
If she wants help, follow her lead- ask her what she wants, and go over the options to get it done. When she is ready and what she wants-it is her call. If you force your way into the situation you may tip him off, and prevent her next attempt to get help.
APS with a consenting adult seems pretty useless to me. They can't force anyone to do anything anymore than you or I could.
Working in the hospital I just ask for a UA and step into the bathroom to "explain" how to obtain the sample. So far no husband has found an excuse to come too, something about women and bathrooms puts them off.