Day 2... after another day of work. Surrounding walls are off. Regarding my question on whether to leave the concrete floating walls in place and just tiles on top, it's too late now. There is no point to return.
The subfloor looks like it was hot mob. What suprised me was that the 4x6 woods around the subfloor was just placed in there with 2 nails into the wall. I could just lift them up by hands after the tiles and mesh were broke off. I thought they should be bolts to the ground.
2x6 wood studs and pipes are in very good condition.
The source of the crack wall problem was because the mesh was too short. The mesh ended couple inches above the subfloor, so there was a short distant of floating concrete without mesh. The highlighted crack was right at the end of the mesh. When breaking the wall off, it was too easy for me to break it where there was no mesh.
I think I did a very good job in 2 days weekends
. I will slowly clean up the area and inspect the drain pipe next week.
