Just realized that the OP was at the same trade show as myself & a couple of other FTers (and 95,000 of our closest friends LOL). Too bad we didn't know; he could have met us for a drink or coffee!
If there had been available space in the overhead I would have been put out as well if asked to gate check, and also would have been angsting on luggage making it with such a tight connection (and agnsting on myself making the connection.
I've had a couple of colleagues who have been forced to gate check even though their roll-aboard was standard size - and luggage didn't make it at all. How that happens w/ a non-stop is beyond me.
Cheers.