The mammoths the bosses drop don't have vendors on them. You need those for this method as the NPCs on it are what your slaves interact with to "follow" you. Regarding getting the mount, if you are horde and don't already have a goblin or are exalted with the kirin tor, they get a 4,000 gold discount on the mount no matter what their rep is, and you could put them in a guild with 10% off for another 2,000 discount. As for dealing with fears, I don't know what you could do there. If you had the etherreal soul-trader it is a companion pet that acts as a vendor, but they are expensive.