This item is acquired in-game. See its sources below.
Not sold on the Auction House·Miscellaneous
An Epic Miscellaneous, item level 421, requires level 70, binds when picked up. Drops from The Vigilant Steward, Zskarn in Aberrus, the Shadowed Crucible.
Infused Quenching OilID 259191 · Miscellaneous"An advanced product utilizing the skills of Alchemists, Enchanters, and Blacksmiths, studying this oil can..."
Items Numbered Next to Venerated Ventilation Fluid
Blizzard numbers items as they are created, so the named items next to ID 202633 (202628 to 202638) were usually added in the same batch as Venerated Ventilation Fluid: the same quest line, zone, vendor or reward set.