Hot take that I'm very open to disagreement on: Charles doesn't care nearly as much about Morality as Edwin does. Charles cares about protecting vulnerable people, primarily (though not necessarily exclusively) His People, which often ends up at the same place as a Code of Ethics, but isn't, ultimately, the same thing. He worries about being Bad, on occasion, but his primary drive isn't to be Good. It's to make sure people he connects to are safe and with him.
Even with his death-incident, he doesn't say "someone was being hurt, I had to stop them". He lays out an explanation of why this particular person sparked a connection in him, and made him want to protect them specifically, when, the implication is, he has not necessarily protected other victims of his 'friends' in the past.
With Crystal, there's a certain part of him that's being naturally protective when he invites her home, but it seems to be sparked on her specifically because he's drawn to her - this is very explicitly (as stated by Edwin) not a service he normally offers to clients, though ghosts are presumably often homeless.
With Becky Aspen, he leans on "you wouldn't let a little American girl get hurt" to convince Edwin, because he knows Edwin will cave to that argument. But it doesn't seem to be his primary motivation (even though he absolutely is down to lay down his afterlife for her once she's been categorized as His To Protect).
With the Devlins - and I think this is the strongest evidence, here, because it's what Charles himself is using to prove to himself he isn't Good - he wants to protect the victims, sure. He is protective. His protectiveness towards them goes way up after they get directly connected to his own trauma, though... and his eventual attack isn't righteous protection, it's pure trauma-fuelled anger. He doesn't throw himself in front of the axe to protect the girls, or try to take it, let alone do anything actually helpful like work with Edwin and Crystal. He attacks because he's pissed.
I want to say very clearly that I mean none of this as an insult to Charles, I love him dearly, and also, again, I'm offering this as one possible interpretation, not as Absolute Fact. But I think it's a viable and interesting interpretation!
(Also super open to "Edwin's not Moral either, he's just combining 'support my case with Hell' with 'my equivalent of protecting people I connect to/see myself in is being kind to people I connect to/see myself in' with 'I intellectually enjoy solving cases and am a conscientious worker'. Which I think is also an extremely viable interpretation! Ultimately both of them would kill an unarmed transdimensional being person without hesitation if it was for the sake of Their People and I love that about them.)
