OP's H ALSO works with BH and OP, but in another department. I fear that if I tell him and he doesn't know he will have BH fired
1) This is a consequence of their choices. They need to be prepared to face ALL consequences.
2) I doubt they'd fire your husband over this and not the OW too.
3) WH swore her BH knows then what's the harm in contacting him to verify? You can do it in a manner that is factual and not malicious. What's the harm?
4) I didn't feel right until I let the BH know I knew. I felt I needed to have that to begin to truly heal.
5). Gently - your husband does not have any credibility on telling the truth. He's continuously lied to you. Why believe him now?
6) he wants to minimize this and protect himself and OW. I say reach out to the other BS and verify yourself. FB or LinkedIn message ?
Good luck. Keep us posted. Follow your gut.