Kathleen, In your first photo you are seeing the edge of the plywood floor. The belly pan has been bumped and pushed in slightly reveling where the plywood sits. In the second picture it is a different situation. The outrigger has sawn through your belly pan due to the floor moving and/ or the shell moving during travel. Being right at the wheel well, you most likely have a leak to the wheel well( a common 1965
issues due to my experience) which has made the floor soft in that area. The result is that the elevator bolt is not holding the structure tight and things are flexing. I would try and get back into that corner with a pick and investigate. The culprit is most likely the elevator bolt right at the end of that outrigger, but the area under the wheel well tub is probably soft too.
It is very common to see this type of damage. To only see it at one outrigger is fairly fortunate.