I have also just checked in to see how you & mini Mae are doing. Great news that she had a poonami. Yay :)
My DD has been on Movicol for years. When things get to gravy like consistency don't stop the Movicol/ whatever medicine you have. You HAVE to keep going at a lower dose for months, if not years, otherwise everything gets bunged up again.
It is nothing to do with little Mae's diet etc. The colon has stretched so much it doesn't recognise normal signals, it needs ages to get back to normal.
If the thought of Movicol for years fills you with dread, my DD is now nearly 10. We both keep an eye on things, she even tells me if I need to give her an extra sachet. It is normal life now, she gets to pick her favourite fruit juice which she loves, she hates being even slightly bunged up.
I'm sure you are very familiar with the poo scale the hospitals have, DD1 still tells me which number poo she had & we adjust diet & movicol accordingly.
One thing I have found, if your DD needs antibiotics for anything in the future you may need to reduce the Movicol dose. My DD1 is allergic to penicillin & I have found the antibiotics she has seem to work as well as Movicol. She doesn't need both, HTH.