I had a different situation, but the story might be of some use.

A female co-worker who was totally nuts was telling others that I had been making life-threatening phone calls to her at her home. (You just have to take my word for it this was 100% bogus and unprovoked. I think she was seeking attention and my name was convenient.)

This became quite a topic and a few people thought I must be doing something horrible. The rumor mill caused me quite a bit of stress.

I let it be known to the office that I had employed an attorney to investigate and sue her or anyone who participated in this slander, even by simply repeating it. This was bogus, I had not even called an attorney. I just thought it sounded good to say so.

The word got around the office very fast and the problem was fixed in hours.

Bumper sticker: Wherever you go, there you are