While traversing my local Better Mineshaft, I discovered this room:

This is extremely unbalanced, as it allows a player to make infinite permanently-loyal villagers selling their various items at extremely low prices (usually 1 emerald, for all but the most expensive trades), for virtually no effort. I will be disabling it in my modpacks going forwards, however, I would personally recommend the feature be removed. Finding this "Workstation Dungeon" completely changes your entire game, and I feel that's too much impact for a single feature from a simple mod to improve mineshafts.

Just disable it then. Also this is a zombie villager room / Abandoned Outpost, not a Workstation Dungeon.