Does anyone know if DOTI is part of the loot table for vault for S4?
It’s not. Only the dungeons in the mythic + pool
dang that sucks 
DOTI hard mode was updated this season to improve the drops of every boss, however. So you can still get a weekly shot at all of the loot at Hero track if you have a group skilled enough to clear it each week. Deios loot also upgrades to Myth if you manage to complete the deathless run requirements.
Just an fyi for those who don’t know, normal and hardmode share loot. So, if you run normal, you are loot locked to hardmode. Found that out last night after killing first boss in hardmode. Was a bummer. 