GrapheneOS maintains 99% android app compatibility. It does not require any additional funding or expenses to support GrapheneOS, and is actually more expensive to add these anticompetitive tools responsible for banning GrapheneOS.
GrapheneOS is also not responsible for bugs in this app. Any bug reports coming from GOS are likely to be from the hardening toggles, which uncover bugs in the app. This is the apps fault, and these bugs still exist on other OSs. It should be resolved for the benefit of all users.