So as it turns out there's a plethora of hats in the game files that don't seem to drop : r/Vermintide
The End Times: Vermintide / Characters - TV Tropes
witch Hunter captain hat cosmetic : r/Vermintide
ArtStation - Victor Saltzpyre: Witch Hunter Captain
Warhammer The End Times Vermintide WITCH HUNTER SET : Leather Hat Baldric with potions and stakes Holster and Pouch included | Leather hats, Hats, Leather
Warhammer: End Times - Vermintide tome and grimoire loot locations | VG247
Witch Hunter Musketeer hat : r/Vermintide
Steam Community :: Guide :: Fashiontide - All hats and descriptions
Steam Community :: Guide :: [2019] All currently obtainable hats and how to get them
Steam Community :: Guide :: Fashiontide - All hats and descriptions
Warhammer: The End Times Vermintide Cinematic Launch Trailer Released
Vermintide 2 content update drops today with Steam Workshop support | VG247
Vermintide 2: Witch Hunter Captain Career – Talents, Builds Guide | Team BRG
Vermintide II Poster - Viktor Saltzpyre – MERCH-USA.WARHAMMER.COM
Witch Hunter Captain - Vermintide 2 Wiki
Save 50% on Warhammer: Vermintide 2 Cosmetic - Purist's Stovepipe on Steam