Aaaaand.... update to the update: my new OMOTON iPad case turns out to be not compatible with the glass screen protector I'd put on it. Because it fits so tightly, it pushes the edge of the screen protector up. Which is not a good thing.
The manufacturer actually very kindly offered to send me a compatible screen protector they make. But it won't get here before I have to leave for my work trip.
So I have one more of the same glass screen protectors (it came in a kit of 2); I'll put it on, go back to the Fintie keyboard case (thank heavens I didn't return it), and see if there's something else I can put in the back pocket of the Synik 22 instead of my iPad.
But I'm bummed.