Replacement image is dissappearing and moving

OK, now can you show me the solid settings and the comp settings and the footage interpretation in AE? I am concerned by the size of the bounding box. It really seems like something is off.

And can you click on the solid itself so I can see what is happening with the corner pin on it and the layer you pasted the data onto?

I also have one more troubleshooting thing for you to try. In your Mocha AE, make sure the surface tool is on and scrub through the timeline, does it look like the surface tool is visible the entire time and does it look like the surface tool is glued to the place you are trying to put the corner pin?