What mount for endoscopic camera do you use?

Apparently you skipped over this part. The camera has to see the entire laser workspace to be useful in Lightburn. The Galvo head is high up from the work area. I am surprised you did not consider this because the camera would be right down on the part if mounted on a S30 laser module.

Your statement…

…confuses me. Why would you want a mounting for the S30 when you have an xTool machine? And if you have a Sculpfun S30 machine, which version? Any mount proposed would depend on this detail.

I suspect you will you will have get ingenious and create your own mount if you still want to do this. Sometimes, a little effort on your part is required.