The mesh network element really in this context is referring to how the Google Pod access points communicate with each other to extend the signal range. It is highly likely the myQ will work perfectly fine connected to this WiFi network without any mesh-related complication.
In the event it doesn't you could simply re-enable the WiFi feature on your ISP-supplied router and just ensure you pick a channel that isn't close to existing Wifi networks (also perhaps including your neighbours' if in close proximity). If your Google Pods are configured to automatically choose their own channels based on best available signal, then I would recommend fixing the channel on your ISP-supplied router as otherwise they will both dance around the frequencies all the time and this could affect your connectivity if your devices don't automatically pickup the channel reassignments (I know from experience that Apple devices tend to struggle with this more than Android).
If you don't wish to see 2 networks all the time, once your myQ is connected you could configure the ISP-supplied router to hide the SSID for its WiFi and all will continue to work fine, you just won't see it in the list when looking to connect to a WiFi network.