Problem with moon is that there's no Atmosphere there at all
In Pluto you at least have Nitrogen, CO and Methane
The moon is actually quite a lot bigger than Pluto, volume of moon is 21,971,669,064 km3 while Pluto is only a tiny 6,387,259,783 km3
Compare that to Uranus's 68,334,355,695,584 km3