This happened to my team, but then we theorized that it was due to the AoE grenades we kept on using, because it only happened on the 2,3,4 rounds and when a person threw a grenade. Next time we did it and no Ogres teleported. We do Oryx on our last character and as a Hunter up top I accidently threw a Vortex grenade out of habit and boom the Ogre teleported. This doesnt make this confirmed, but it was pretty darn convincing when we stopped throwing grenades, the Ogres stopped teleporting