Android Auto and GrapheneOS

Hi! I've tried many methods to get CoMaps to work with Android Auto running GrapheneOS, but I just can't get A.A. to even recognize CoMaps exists. I tried a secret and hidden Android Auto settings menu and I tried redownloading CoMaps from Aurora instead of the apk... both to no avail. Does anyone else have pointers? Apologies if this isn't the right place to ask!