I am so sorry to hear about your travelling experience with your furbaby . .I travelled over the holidays with 3 furbabies with me, 2 of which have never flown and they were all well behaved . . .Tiger was supposedly going to be taken to a containment area that has the same cabin temperature but somehow he sensed he was going to be separated from his family so he was angsty and whiney on the drive to the airport up to the counter . . .I begged the lady if I could just take him with me to the cabin and he and Parker can share a bag and she okay'd it and I tell you Tiger was completely quiet from them on.
Perhaps you might want to bring a favorite treat that will take him a while to finish like bully sticks so he will be preoccupied with it . .also, maybe you can take him out of the carrier until before boarding so he knows you are always right there with him . . .don't give up on the little guy . . . he probably just does not know what is going on. . .