The grenade launcher in the first picture is based on a Milkor MGL. I'm not sure what the CAW one is replicating.
It IS a Milkor. MGL-140 to be exact. DoD is calling it the M32, and the Army might get a few.
With regards to the rail, it DOES look like an VLTOR product. I've also seen some with a Milkor-produced intgrated forend, with removeable rail sections.
The stock/stock angle coupled with that optic height looks very awkward. I'd prefer the stock of the MGL Mk1 because it places the buttpad higher in relation to the bore and glass. My M16/M203 has a Docter on the side quadrant sight and it works like a charm. I prefer that to top-mounted optics and leaf sights for GLs, but it's also snagged easier on your kit.