I bought a used shield and don’t have to option to do anything other than wait for access. I called them earlier and they said that since I bought a used shield there was nothing they could do.

If you have a Shield you should get instant access to Geforce Now as it is included with the purchase of a Shield.

Geforce now you can buy a key for a few dollars for instant access.

Shadow you better off asking here https://www.reddit.com/r/cloudygamer/