I'm attempting to use camera tracking on two similar photos to determine focal length and orientation and, subsequently, to reconstruct the scene with geometry. I've tracked all points manually, since there is too large of a perspective change and only two frames. I appear to have gotten a very good solve, with an average error of 0.1334. However, after orienting the camera (set origin, X axis, etc) and trying to match geometry, I realized the focal length was slightly off. The focal length that Blender calculated matches that obtained from fSpy. I also tried a few different focal lengths to verify that I had the lowest error value. I have also tried adjusting the focal length and re-solving to get the trackers to match the geometry, since it's a simple shape with right angles, but with no luck. I believe I've had this same issue after almost every successful camera solve I've gotten in the past. In fact, I think I've only ever gotten one decent camera match, out of numerous attempts over the last few years.
Would anyone be willing to take a look at the file for me and tell me what I'm doing wrong? I would really appreciate it! Here are the images I used, as well as some screenshots.