I'll never understand the idea that some folks have that anyone at the airport has the ability to mess with your sights and/or rifle. It's in a locked case when you get to the airport. It REMAINS locked unless the ticketing agent has you put the declaration form into the case, or, when TSA has you open it for them to inspect it. At no point should anyone have the keys to the locks, except for you. I'd also have to imagine that 99% of folks who know how to actually change a scope's zero are also the type of person who would not inherently mess with another person's rifle.
Of course, I can see where someone might mishandle the case, knocking it around or dropping it, but no one should have the ability to easily adjust your sights. Makes me wonder if it's just an excuse for bad marksmanship, or, folks have never heard of Locktite when mounting a scope.
But as anyone should, YES, always check your zero after flying, taking a spill, mishandling, etc. As for me, I'll be flying with a paper target and sending 3 rounds down range to check my zero once I hit public ground and need to wait until the next day to hunt (I'm getting dropped off via bush plane).
Best of luck to you on your hunt!