Front floor water damage need to remove heater-seats

Well I managed to get the front bench seat out, remove the water heater and take off the flooring all the way to the door. The floor is saturated and delaminated at the front. It looks like the water was entering along the bottom front seam due to some undetected damage that opened it up. Looks like someone backed into the front of the trailer and made a small ding. Enough to cause a gap.

Now to see how to repair the floor.