I think that the entire remaining spillway parts have been severely damaged. The “West corner” appears to have shifted significantly as you observe. As far as the bolts being driven into the floor, did anyone see a drill rig out in that area(?) or was it just some guys with hand held units. If it was a human held drill process then they are way undersized and probably not deep enough for them to remain anchored for a significant period. I also think they are kidding themselves with the sealant work. Getting good adhesion on concrete even with modern day sealants is tricky at best. The forces involved with that water flow are immense and the sealants are bound to fail sooner rather than later.
The discharge rate of the water at the drain outlets seems to be increasing as time passes. At some flow rate it will do more damage to the supporting ground under the spillway and another breach in the floor will appear.