First hand: Perfect.
Second hand: That turn card screws you over bad. If he had AK/AQ, KK, or QQ (all likely 4-bet holdings) he's now in the lead by FAR. It's clear to me MP1 doesn't have an ace. UTG you said was a maniac, but I'm not sure if that's pre-flop as well as post-flop.
If he's a maniac pre-flop as well as post-flop, then you have to raise that turn. It's likely one or both of them are still drawing. If he 3-bets you'll have to call down and hope he was overplaying something like TT, KJ, or a straight/flush draw. In a pot this large, you cannot give up such a strong holding to a pre-flop and post-flop maniac. On the other hand, if he's only a maniac post-flop, you can dump on the turn easy. There's no 4-betting hands you beat.