The bug
Ridden camels need to be equipped with a saddle before they can be moved by mob control which is inconsistent with other rideable mobs.
Steps to reproduce
Use the following command:
/summon minecraft:camel ~ ~ ~ {Passengers:[{id:husk}]}
/summon minecraft:horse ~ ~ ~ {Passengers:[{id:husk}]}
Mobs that don't need to be saddled:
Horse
Donkey
Mule
Skeleton horse
Zombie horse
Confirmed.