The plumber's scanner guy did an ultrasound on our floors to find the leak, and it turned out that my vanity and all my floorboards had to come out, along with some boards in the hallway, the hall closet, and my bedroom. The plumber was able to jackhammer out a pretty small hole to get to the leak. That's the newer gray square to the left in the pic below.
All the cork flooring in my bathroom has to be replaced, but cork is easy (and we were able to order the same cork as before). In the meantime, of course, my pot sits in my tub and the floor is nekkid.
Speaking of the hole, here it is (two shots of same):
By Thursday, the leak was fixed, the wet areas were drying out (we had big fans running day and night since discovering the leak), and we were able to move home after only six nights in the hotel. Sister A. was even able to do laundry at home that day. We were sure glad to be back in our own beds with our kitties, who were slightly freaked out from all the repairmen and neither of us being home at night.
My vanity is a little warped at the base, but Frank the Handyman says he can sand it down, paint it, and it'll be fine, so that saves us replacement cost.
The floorboards we ordered have already arrived and Frank picked them up for us today; they're now acclimating in the kitchen. Minnie has inspected all the materials--she's very efficient.
Frank will start work on my bathroom and the flooring in about a week. I am soooooo looking forward to having my bathroom back!