It will directly wire to the laser, but personally, I used the adaptor board. It provided plug-n-play, with no wires cut or soldered. I did have to extend the PWM control from the Rambo board to the companion board. And, after hundreds of hours of laser use, I started to get arcing where the laser plugged into board. I write about how I rewired the board here.
But the companion board is not necessary. I purchased one of the $79 laser engravers when they were available and written about here. For use on that machine, I wired the module directly, and it works just fine.