Creating a Google App signing PEM from Xamarin Keystore

I tried to provide a PEM file to Google so that they can re-key the app signing in Google Console.

This is the command they want me to use:

keytool -genkeypair -alias upload -keyalg RSA -keysize 2048 -validity 9125 -keystore MYALIAS.keystore

However, I want to use the Keystore in Xamarin so that I can continue to publish, archive, and sign through Visual Studio. If I make a new pair with their command, can I only sign using the Android Studio tools?

So I removed the genkeypair tried this:

keytool -export -keyalg RSA -keysize 2048 -validity 9125 -alias MYALIAS -file MYALIAS.pem -keystore MYALIAS.keystore

But, they said that the PEM was not compatible.

What keytool command can I use to keep using my Xamarin keystore while meeting Google's requirements?

Do I need to include the genkeypair if I want to keep using the Xamarin keystore?

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