Hey there IpadTTDI,
We'd like to help get the audio from your Google Meet screen recordings working right.
Before we start, we wanted to provide this link as it explains that some apps may not allow you to record audio. You would need to contact the app developer(Google) to confirm this. Check out: Record the screen on your iPhone, iPad, or iPod touch
Are we correct in saying that none of your screen recordings, even ones of your Home Screen, do not include audio from your mic? If you haven't tested this, please do it now.
This link shows how to Restart your iPhone.
Another thing to rule out would be being outdated. For your iPad model, the latest version is iPadOS 14.4. You can verify which version number is installed within Settings > General > About. Here's a link that'll show how to first back up, then Update your iPhone, iPad, or iPod touch. Afterwards, this link shows how to Update apps or use automatic downloads.
Take care!