While, not the healthiest feeling in the world......um totally understandable. Four years out for me and I'm just to the point where I wouldn't stop someone else from peeing on the OW if she was on fire. She was a friend. I also second the thought that if you're working toward reconciliation it is a seesaw of emotions, hating the AP and then realizing that hate pendulum swings back on your FWS. At 1 1/2 years....I still felt white hot rage.
Being associated with HR, BODs, and humans.....we could care less about what happens behind closed bedroom doors, unless it was an HR issue within the company. This is fairly common behavior. Half of the population is touched by some kind of infidelity. Doesn't make it right or easier to deal with, but common. It is none of their business. If some non-employee or vendor approached with such a story, it would be more of a reflection on that person....and gossip mongering. I'd stop doing business with them if they were a vendor. If a non-employee.....I'd completely ignore it. This smacks a bit of your FWS not wanting to acknowledge the consequences a bit. There are other companies, other jobs. It is a small price to pay and honestly, if the BOD fires your FWS, a consequence of her choices not yours. That is her burden to deal with.
In our case the A was outted by the OBS who told me. I suspected, but never found the evidence. He did. I have a weird gratitude for that. And, a much better marriage for the work that FWH and myself have put in. That being said, everyone knows. My family, his, our workplaces, friends, bank, etc. We're just short of screaming it from the highest mountain. Those people told people. He's felt the shame turned into guilt and turned that into action within our marriage. It was/is real work for us both. But, we are reaping the rewards. And, the people who are real and genuine in our lives don't care. They see what we're doing and support us. Tell the OB before she makes the uninformed decision to commit herself further to him. In the end, you'll sleep better at night.
OBS has tried to thwart our recovery a couple of times. But, his ex didn't do the work. I'm sure he feels that my FWH has gotten off without the consequences, but he hasn't seen the work. OW continues to deny that this was anything that she has any responsibility over.
Take care.