Red Letter Media/WMG

The timeline split at some point and created the two different Plinketts.
In fact, you don't even exist anymore.

Stoklasa's Plinkett is the grandfather of Evans' Plinkett.
Stoklasa!Plinkett's son killed himself when he realized how his son ended up like his father.

Plinkett is possessed by a violently misogynistic demon, and the two repairmen are his unknowing disciples.
This would explain Plinkett's superhuman abilities as well as the repairmen's apparent compulsion for spending so much time at his house, reviewing movies.