The Tormentors are not all that bad, annoying but not hard. Its not like two massive hive knights that spawn inside the ADU circle! Just draw his agro towards your best decoy then kill adds and/or put shots on him. If your teammates are stupid enough to jump to the ADU than one person, with decent heavy supplies and good add clearing can deal with the adds by themselves, at least sufficient for the needs. If your teammates fail at killing the tormentor rapidly due to lack of using supers and/or just knowing how to take one down, well I just hope your not level 40+ in legendary before starting a new run.