I think you’re missing the point. Either that, or you have the only GF that can’t repeatedly cut in the same place with no input file changes.
I have rulers cut from a full sheet of draftboard, and it sits snug against the front and sides of the tray edges.
Although the camera is nowhere near close across most of the bed, I know exactly what rule marks on the edges of the UI match up to my cut/scored rulers. If I put an object in a precise location, and re-cut from there, it is a perfect match.
Look at the orange circle - I aligned the source image exactly at the center - 10" mark in the UI. The resulting cut is nowhere near in the camera image, but if you look at where the cut meets the ruler, it is exactly in the right place on the bed.
If you cut a jig and locate your pieces relative to the jig IN THE UI, ignoring the camera, it will always be perfectly aligned.
If you’re making a lot in quantity, then have a template image that cuts many shapes from your jig material, then ignore that cut image when you add the engrave, and align to the image in the UI, NOT the camera image from the bed. Sometimes I do my alignments with no material on the bed, because the black background makes it easier to see the lines…