The mass murder of the civilians of Vault 111 is attributed to his predecessor (or one of them). There is the possibility the pscyhopathy is institutionalized, or at least pervasive enough there's a reasonable enough chance of pscyhopaths being reared within the Insittute that more than one Director in the last 60 years has been one.
I am not inclined to give them the benefit of the doubt, but that's personal opinion, and others may.
I see a lot of wild speculation with no foundation in any presented facts.
Having no sense of wrongdoing doesn't make it any more right. That Brian Virgil understands and is cognizant of how unethical the research is, to the point of actively sabotaging it and escaping, shows that the scientists of the Institute understand ethics (and ignore them). They have numerous members in their ranks that either have experienced the Commonwealth somewhat, or were born and raised there and understand exactly what the folks above are like (Madison Li, a division head).
Hancock's a junkie, yes, but he's never treated as dishonest. He's brutal and at times ruthless. This revelation also comes during one of his 'approval' scenes with the SS, meaning he's more likely to be honest, not less.
And releasing a group of psychotic, cannibalistic rage monsters on the Commonwealth to 'motivate' them is exactly the type of stunt a psychopath would pull. For crying out loud.
(Also, I didn't say 'simple' beating, I said 'savage', which implies brutality.)