Oh my gosh that sounds absolutely horrible! I hope it won't come to any of that because this is summer season picking up and rentals/hotels will become unaffordable very soon now. For us it's ok as long as we can use our second bath room but not if it turns out that water from the washing machine and kitchen cause water damage too at his place. Let's hope this is not happening.
Meanwhile I make sure to tidy up while I still can I expect that they need to open up the whole bathroom and bath honestly, but I'm not a plumber.. Grateful to have a second bathroom.. :)
You're welcome and have a good week over there <3