Sounds like you have a scaling issue. I suspect it is in your workflow process, but we need to make sure the rotary settings are correct.
I recently did a “study” with my rotaries and put it in a posting. Try following all the steps I outlined for your rotary type, and then see if it works for you.
Basically, if it is 75mm in Y in your drawing, it should wrap 75mm around your part. If the rotary parameters are not set accurately, you will get scaling issues.
Not sure why you are doing this, or what you really mean, but it sounds like an unnecessary step. If you are actually using an image file instead of a raster, I think doing an image on glass would be very difficult. You do not get a more burn, less burn like on wood. If you upload the image, maybe we can better understand what you wish to accomplish.