What proof do you have???
This Doctor is likely an operator. He'll deny, deny and deny any and all wrongdoing. WHEN (not if) you expose to his wife it would help greatly to have undeniable proof. Copies of emails, recordings done with a voice activated digital recorder, anything.
Won't matter much though as I think the likely outcome is that your wife will get fired. His wife and he work in the same office. His wife will mostly demand her removal from the workplace whether he denies it or not. THIS IS GOOD. You want your wife out of there anyway and when OM doesn't defend her and tries to put ALL the blame on your wife for the entire affair she will hopefully become aware of just how used she is and how bogus the relationship is.
Here's a little link about affair exposure. If you read through WAT's thread and the links you should find all the information you need.
Wat's Affair Exposure 101 On cursory review it appears you may need to catch up with his wife when she is at home and out of the office. You don't want any confrontation with OM so their office is out. Face to Face is the best and offer her a envelope with copies of "evidence" and/or offer to let her listen to any recordings (if these recordings were done illegally do not give her a copy...only offer to let her listen to yours).
In the end you may end up with a nice sexual harassment lawsuit. He should settle up pretty quickly however doctors are notorious for fighting things out to the bitter end as they have the money to prolong the fight and feel entitled to disputing even obvious claims.
Finally, predators come in all shapes, sizes and colors. OM's race means absolutely nothing. It does not make it worse than anyone else on this board and emphasizing the interracial characteristic of your wife's affair only makes you sound racist. If you continue emphasizing the race factor you MAY only limit the responses you get herein. I realize you are hurting and lashing out and beseech you to realize that this board has members of all races from around the world. This factor may be more significant in your locale and you can address that issue carefully and tactfully; however, straight racism makes you sound like an a$$. YOU are better than OM because you are a faithful and loving husband, individual and father...NOT because you are white.
Mr. Wondering