The Vet Karka has two phases. At the end of phase 1 (Armored), it currently allows downed players to revive and provides all of the xp.
At the end of phase 2 (Cracked armor), or the karka death, a player can loot the carcass but they do not receive any xp and a downed player is not revived.
So by killing a vet karka halfway (end of phase 1) a player can get all of the experience that a vet karka will provide. I think people want the loot but this can be more of an issue in the future.