ULPT: I need to avoid working with one person

I had a personal incident with a person at work a few years ago. I became 100% WFH shortly afterwards and never worked with them, so it didn't matter. Now they might get a promotion soon and I might occasionally have to talk to them. Without diving into this topic too much, this is not going to happen. If I have to do that, I will have to quit. The thing is, I am very established in my current work environment and have a good career going. This other person is coming in as a very junior person and nobody knows them yet. I know if I told my employer "It's me or them", they would choose me. But I CANNOT tell ANYONE about my falling out. So what do I do? So you see any (unethical) way to stay in my job and avoid that person?