We have similar issue, we have implemented app logic via google federated login, the app shows available google accounts on the device, user selects one and proceeds to access the restricted area of the app, no password required,

However for this, google tester needs to access his own google account, since this account could be from anyone, its not clear how to bypass it on the server for the second step screen for a static OTP for mobile number verification.

I dont understand how to allow google testers to bypass federated login via google and skip any additional checks on the server