I specialized goblin engineering, and have done the quest to unlock the cross-specialization vendor where you get the gnomish engineering vouchers at the racetrack in Thousand Needles, but the Gadgetzan teleporter recipe is missing.
Please add it as well as any other recipes that might be missing. I assume the everlook one is missing from the gnomish one as well, since that one is also learned from a teleporter NPC.