Did it twice this past fall, with no problems whatsoever. Both times I paid $75 for an extra Southwest bag. In full disclosure I did leave some elk meat behind both times, but brought over 100lbs of boneless meat both times as well. It's really not that difficult as long as the meat isn't bloody/leaking and is frozen. I do one cheap Walmart cooler with ~50lbs of meat, throw another 10-15lbs in my suitcase, and throw whatever I can carry in my carry-on 24-can soft-sided cooler (usually both backstraps, tloins, and some brisket/trim. The rate-limited step for me isn't the baggage fees, but simply being able to carry all that meat. I live in MD and rarely have a direct flight and ALL my meat has made it home safe.
Driving home solo back to the south east. Can cable lock antlers into the bed of the truck, but that's not much of a deterrent if someone has bolt cutters or hack saw. They'll have them in less than a min.
What to do if needing to go into the store to buy dry ice, gas station bathroom, etc. with antlers cabled in the bed? At night a motel will be rented and they will be brought inside.