Nostalrius Begins - Quality wow vanilla realm (1.12)

During the second stage of the "Taming the Beast" quest chain, I was unable to tame the second pet, a Nightsaber Stalker. For some reason every time I target a Nightsaber Stalker I get an "Invalid Target" error. I've tried to tame every kind of Nightsaber, abandoning and re-starting the quest, re-logging... anything I can think of, and nothing. I went so far as to have another hunter on the same step of the quest capture and then abandon a Nightsaber Stalker, and I was STILL unable to capture the one which had just worked for him... Any ideas?

worked! thanks so much