Merry Christmas! Alignment simply doesn't perform the correct transformations either from mount to sky or sky to mount, after syncing it with 4 points. My observation site is fairly constrained, so I'm not able to do a full east/west sync point or north/south sync point.
To accelerate testing, I created a function to inject sync points, and set it up as follows:
Neither the nearest plugin, or the built-in can consistently map the sky or mount coordinates against its physical location, but the SVD algorithm seems to do well (with limited testing).