Last time i checked this was a story dungeon.As in it was designed for story and thus being a new player dungeon.I dont recall reading anywhere that they have changed the dungeon to be a place for level 70 players to farm tomes.The tomes are just there as a reward for older players participating and helping the new players clear content in the way it was designed to be enjoyed.
I havent seen any notes anywhere from SE stating it's ok to use a glitch to either force other players to use the same glitch or to deny new players of participating in the story content ie the boss fights.

Too many self entitled high leveled players in this thread who only seem to care about themselves and contribute to the toxicity that exists in duty finder.

Hopefully SE will start banning these players though i'd say they will only be able to ban players who have repeatadly broken the TOS with this glitch as players can get random disconnects from network issues and it would be bad to accidently punish them also.

The game is designed for new and old players and older players need to start remembering that because if you keep up the toxicity towards newer players you wil drive them away and eventually the game will start dying when older players leave and there are no new players to replace them.