Any files accessed within Google Drive, from the native Files App, are entirely and totally dependent upon the [installed] Google Drive App for all feature support. This applies equally to other Cloud service providers - who similarly require their own App to be installed to act as a “bridge” to their services.
If you’re unable to access or consistently edit any files within a Cloud service not provided by Apple, you should look to raise a support request with the relevant Cloud App Developer.
As a workaround, if you copy the file to your iPad local storage (or Apple iCloud), you can edit/markup from there - then copy the edited file back to Google Drive when you are finished.
I hope you find this helpful in addressing your issue to appropriate sources of support - and in providing an effective workaround solution.