It appears that luck was on his side.
The seller of the Tier 4 Rejuvenation Pill wanted five Epic-Rank Accessories that could stop mind-controlling abilities like charm skill, hypnosis, or illusion. Furthermore, a couple of Pseudo-Legendary Accessories that have related abilities can also be accepted as an alternative.
If it was the latter, the seller promised that he would also concoct Tier 4 Pills for the buyer as long as they provide the ingredients. This promise can be used three times!
Offering two Pseudo-Legendary was indeed tempting but for it to have a non-combat skill, it would be very difficult to find them.
It's easier to find weapons with offensive skills than accessories with support skills after all.
Of course, this isn't a problem for Vincent who had hundreds of high-level items in his Obsidian Treasure Box.
He has a couple of items that have reached Pseudo Legendary with similar effects.