So your guild is stuck on Teron because you have some noobs that just cant kill their constructs? Yeah every guild always has a couple idiots that cant seem to get it right and because of that, everyone groans and complains as soon as that person is targetted, cause u know theres gonna be constructs running in the raid killing your healers.
This exploit is simple and will ease your pain. When someone gets targetted that you know is gonna have trouble killing their constructs, just make them hearth out immediately. Their constructs wont appear and you can concentrate on killing Teron. Usually just a couple people need to hearth out and you get a successful kill.
I know it sucks cause then they dont get loot, but its either that or wipe, wipe wipe. Usually after you down him a few times, you can let them stay in the raid, its just getting that first couple of kills that really help you learn the whole fight.
I expect Blizz to fix this soon by either preventing you from hearthing out, or making your constructs appear anyway after you hearth.