Could it be possible that Gabriel has a twin identical brother? And that twin brother secretly loved Adrien's mum but Gabriel got to her first? What if when she disappeared that brother got so upset that he became hawk moth *mind blown*
Which do you prefer? Can I just comment that it looks like they're house shopping? "OH, how bout that neighborhood? No, to far from the action, what if something happens and we can't get there in time? We could go this way?