I think Ferid will do neither. Whatever past he has, he doesn’t seem bothered by it; on the contrary, he seems to be quite eager to share his story, even suggesting it himself. Considering what he’s been doing for ages (killing kids like it’s nothing, orchestrating very cruel and twisted downfalls like he did with Crowley), it appears to me that he had long since lost any capacity to feel emotional pain from pretty much anything, including a dark past, even his own, which means he’s just incapable of breaking down or going berserk from that.
If you want my opinion on what can impact him enough for him to get furious, I’d say it might happen if his pawns or someone he considered far below himself outsmart him or his plans go awry in a way that makes the situation actually better for everyone or makes people happy, and he can only watch, unable to play his twisted mind games; he seems to be incapable of accepting that.
As to the reactions to his tragic past… seeing that all the three you mentioned are smart guys and suffered through hell themselves, there will be little compassion offered by them, simply because they all seem to be the type to believe that a tragic past can explain the hideous acts a person commits, but it can’t excuse them.
Crowley expressed that he was interested to know how Ferid became such a complete monster, so his intellectual curiosity will be appeased as he learns about the reasons, but at the same time, it remains to be seen if he will find them satisfactory enough for what Ferid became; plus, I doubt it can make him anymore condoning of Ferid’s methods. The most Ferid can hope from him is probably something like, 'yeah, you’d gone through a lot of shit, but that’s no reason to put others, like me and my comrades, through a hellish nightmare, like we didn’t have enough of that without you adding to our suffering.’