Combine dates it to after Rallos Zek invaded the planes of power, after Green Mist wiped out the Shissar on Kunark, and after the gods cursed the giants, trolls, ogres, and goblin for siding with Zek.
Antonica is name given to the continent well after the fall of the Combine empire. Name change was made to honor the founder Qeynos Antonius Bayle I. Before that it was called Tunaria.
That teleporter in Feerrott is of Shissar origin. The combine do remaster the knowledge of how to use them. Then knowledge is lost again with fall of the Combine and then rediscovered again by Al Kabor in original EQ.