But here, he openly said they weren't going for the world boss. Just kept tagging it to prevent the others from getting the kill on it.
So what I am guessing is:
The Republic team gets wiped while fighting, they come back to attempt again. As they go in, the Imperials tag the world boss first and the Republic team runs off to reset it (or whatever) they get wiped. Rinse and repeat. Sounds like harassment to you? Does to me. I am betting this is what happened and the OP is not telling the whole truth. Then they get a warning for just tagging a boss to prevent the other team from doing it. notice how he said after awhile they all left. No intention to kill it, just to harass. Now if the Republic team was smart they'd get more people to help wipe them out over and over. But whatever.