I'm having the same issue
Meshtastic
A community to discuss Meshtastic (https://meshtastic.org/docs/introduction)
Other mesh communities:
MeshCore: !Meshcore@feddit.org Reticulum: !Reticulum@mander.xyz
https://meshtastic.org/docs/software/android/installation
TL;DR: Use F-droid
Looks like there are other .apks out there too, but I'd just stick with F-Droid since you're already on Graphene and F-droid is a handy repository. Just be careful about what you install and where you source your apps.
I think they have the app but the map doesn't work without Google play services enabled.
That'll probably be the case regardless of where you get it from then, unless there is another variant or fork that uses something different like OSM or whatever.
Hey
Just create a new profile in settings
Install the google api (sandboxed) option that comes with graphene
Then install f-droid from graphene
Use f-droid to install aurora store
Use aurora's anonymous mode to install maps
Et voilà