It's not that no one was wanted to do this, I think the outcome will be questionable. Shavings from milling will cause problems with 3D printing. Smoke from a laser might also cause problems with 3D printing.

Also, using a cantilever arm for milling is questionable. It should be a gantry, in my opinion. There is a very good reason most CNC routers use gantry mechanisms, even if they are only intended to hold 1/8" engraving bits.

A mechanism rigid enough for even light milling will likely weigh down and reduce the effective 3D printing speed and quality.