Previous notes suggested that the above mobs could spawn at Nort's Field (circa 2020); I've checked there multiple times and have never seen either one there (2023-10-07)
I have no idea why you would go to the trouble, but they can also be dismantled from BooBoomba's Lucky Charm though you need an L3 device builder present (non-tradable) and you need 2+ of the devices to analyze and then dismantle for the Bloody Jenquai Student's Head