They shouldn’t have put them in a room with a work order on it to fix a shower such that they wouldn’t be able to use it for hours. This is all traceable in their computer system and I’d be arguing for being reimbursed for that night.
The mouse. That’s awful, but pests are not 100% in Disney’s control. They could have asked to move rooms once that was discovered, but honestly, I’m not sure they would have done anything else. Doors are left open by guests and housekeeping. Could have unknowingly picked up the mouse in a park or in other luggage left with Bell Services. Disney tries hard, but creatures live everywhere and even with solid pest management, even the animals know Disney is a great place to be. Everyone - birds, ants, squirrels, mice - all love free food. I literally watched a crow drink from a cup on a stroller last trip.
The MB problem is a common nuisance. And the phone app should work, even if the MB doesn’t, and you can have the band fixed later. It’s wise to inactivate MBs on your account if you have a bunch and just leave 1-3 per person on the room active to have that be more reliable. Once I cut to only having 2 or 3 active bands, I haven’t had the problem since.
My recent stay in a CR garden wing room was excellent. It was spotless, ready early, quiet, everyone’s band worked, fully stocked with expected amenities and towels, and totally met our expectations. Now yes, I’ve had Disney rooms with peeling paint, hair in the shower, non working HVAC units, missing lightbulbs, missing towels, wet carpet, horribly loud other quests after quiet hours, and a frog as a guest. But Disney did make it right every time.
OP, I agree that this experience was crappy for you. Multiple things went south for you and that stinks. I would have been super angry myself. That shower issue would have sent me to the front desk asking for them to move us. But it can happen at any resort and remember to complain appropriately at the time. Hopefully your next stay at a WDW resort goes more smoothly!