I flew United last year and on my return flights, connection in Frankfurt was cancelled. They got me sorted out within a few hours with added stops, but such is life. When I arrived in Chicago and did customs, no bags or rifle. I had an air tag and later when I finally reached Anchorage could see my rifle was in New Jersey. After it didn't move for a few days, and lots of calls without response, was worried it was lost/stolen and I was just seeing the airtag in some bin or trashcan. Rifle finally showed up, new locks without keys, had my Global Re-entry revoked because no 4457 presented with the rifle. My old locks they cut off were just tossed into the case with my Rigby, but end of the day, it all worked out.
Somehow the cut locks didn't even ding my stock, I was able to grind off the new locks they installed, CBP when I stopped to get a 4457 for another rifle checked into the Global Reentry, had it fixed and apologised for the error on their part, a quick review of things on their end showed I entered at a different location and they showed a 4457 issued to me.
I think it is reasonable to fear loss or theft of a dear and/or expensive firearm. I have insurance on several of my more expensive fine rifles and doubles which is worth the piece of mind for me.
And totally agree on flying Qatar. E-mail their special services at least a few days before departure, and they already have things noted on your booking. They have been great, flew with them in May to JoBerg and just again last month to Harare. Get a nice break in Doha with an airport that has all kinds of lounges, sleep pods and three actual hotels. Qatar has your bags and rifle during the layover, so no hassle or fuss, then arrive at destination early morning and have time to make camp whether several hour drive or another charter flight.