Are you talking about back flushing or an internal tank flush?
From your description, it sounds like the latter. Which would have been the first go to if you thought the poop a mid was gettin ya.
You probably didn’t have any issue at all. And the flush kit (if that’s what you’re describing) just cleaned the sensor and of course it’s going to clean some solids that otherwise would not be in solution or suspension since the camper has been stationary.
Fwiw you didn’t say you had a tank flush kit on it. Hence my recommendation to fill it up a ways and drive it around = poor man’s black tank flush tornado!
Glad your back in the business of peaceful #2s!