Wireless charging is part of the Enhanced Convenience and Driver Confidence II package. It's a $3575 option on the RS trim.Only available in Premium models unless you request the RS to be loaded with it. Least as far as I know. I have the RS, but no wireless charging, just USB ports. Chevy doesn't advertise the wireless charging for the RS, it's just an added feature.
Seems, dealers will build a certain number of vehicles, all with different features to try and upsell the vehicle. Case in point, my RS, comes with the full sunroof, but I have looked at other RS models, and they didn't have the roof. Same with the interior, mine is black on black. Seen another RS, same colour as mine, but it was two tone.
But back to case in point, you can easily added the wireless charging, though I'd recommend having the dealer do it, as you got to run and splice wires into the dash.