Only other thing I can think to try is uninstalling from the normal app management system. That may only allow you to uninstall updates, but it...
Yeah, the Pro toolbox adds a ton of functionality, Definitely worth the cost of a Starbucks coffee IMO.
Make sure you're going to "Manage System Apps", Gmail was near the bottom of that list for me.
You, sir, are a gentleman and a scholar, and deserve to be the recipient of over 9000 internets. Hats off and good day!
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