I believe I have had this happen too, on official pvp server #1098.
Because its official and I cannot fly, I cannot confirm that its indeed one of the crafters, but it sure looks similar. It does not appear as a map marker, but it could be someone elses.
Ive also had my crafters which were placed AFTER the AoH update, vanish from my base one by one. The number keeps geting smaller every day as Ive not added any new ones.
