Yeah I do remember that. It only took about 7 visits for her to decide I was worthy enough to pet her
At this point I would look for a pattern. Does she only poop there when other people visit? Also look for any changes in her food intake. Does the consistency of the "misplaced item" look normal?
It's not revenge, that is a myth......A wonderful holistic vet explained this to me when one of my cats was pee'ing in every box, suitcase, the tub, etc, instead of his box. He was uncomfortable in his box so he looked for an alternative box, blaming the box on his discomfort. The discomfort was brought on by stress. The vet said stress could be brought on in some cats by changing the brand of litter, the food, even the dish the food is put in, or the place the food dish is set down. Some cats need perfect consistency.
We also started making the food for him (he was on a urinary tract diet, vet prescription only, very expensive) and I bought 12 bowls for cat food so even if I break them he could have the same dish for years. We experimented with 3-4 catboxes and litter types to find out what he liked and then where he wanted the box. He hasn't thought outside the box in almost nine years now. We were gonna have him put down back then, too, it was so bad.
I know I've told this story before, but your kitteh's poopin' issues sound sooooo familiar.