I haven't hunted carabok for a while but I was told that "something is going on with them". Gallards on the other hand I do swunt and I haven't noticed anything different with them other than they have been slightly more generous in loot this month.
MindArk added something a while ago that makes mobs when they spawn ignore you at first. Mixed with the delay some mobs do where they move backwards away from you at first sign of them starting agro it most likely can be confusing for the mob. I have seen similar before on them but not for that long.