My Mom was doing so well going to the Bathroom, by herself. And I was getting up with her 2 or 3 times a night and early morning. Plus, I was not sleeping well. I decided with her agreeing, to allow her to go to the bathroom during the night by herself. She said she could do it and she is very good and stable with her walker, the bathroom is right by her bedroom. So far it has been 5 nights and things have gone well. I hope I am doing the right thing, it sure seems to be helping me with my sleep pattern.
When she goes in there, does she actually use the bathroom? Is it urine? Does she have frequency during the day as well? Is she drinking lots of fluids? Has she been checked for diabetes? Just before I was diagnosed with Diabetes, that happened to me. Sleep apnea can also cause it. Are her meds causing this to happen. I might discuss it with her doctor to see if you can stop it.
I would hate to argue with a good arrangement, but I would say that people with dementia often have mobility problems, balance problems, etc. Falling and fractures are a huge concern. I'd keep that in mind.
Also, I wouldn't rely on what she may tell you, because she may forget what she says or promises you the minute after she does it. Most people with advanced dementia may agree to anything or promise anything, but they aren't able to live up to that due to the damage to their brain.
Please let us know how this works out.