I think we need fresh sets of eyes (and noses lol) to figure out what's going on with Honey and how to address it. This has happened several times now. She goes outside multiple times a day (OH is home all day and goes out frequently, probably every 30-45 minutes, and she goes with him) and has a wee and sometimes poops. Sometimes, though, most recently last night, she goes out, wees, and comes in only to poop inside, always in my son's room. We're at our wits' end with it.
How frustrating... Try feeding her her breakfast and dinner in your son's room. Do that for a week or so. Dogs don't like to poo in what they consider to be their dining room.