Well, my DW has solved the toilet filling problem. As I wrote earlier my Dometic 310 was filling much higher than what I had seen as normal, my concern was a potential flooding issue.
We are currently camping with our daughter, son-in-law and our 4 year old grand daughter. My DW caught her filling the bowl with the foot pedal, she has been going into the bathroom on her own from time to time and playing with the pedal, hence, filling the bowl the process. When I would check the fill rate and the stoppage of the post flush trickle, everything was normal. Time to time checking the bowl I would find it almost to the rim...concern.
The little culprit confessed after being caught in act...40 lashes or hugs. ;-)
The Millers, enjoying life, spending the kids inheritance.