I watched r1 again just for good measure & agree that it was close, but Merab won. O'Malley's likely having a bit of fun to make a point that it was close enough for a rematch. I agree.
O'Malley was pulling away from Merab before the 1st TD, & landed the biggest strike of the round, but Merab was very active in striking when he took O'malley down & some of them were pretty big strikes.
I'm a believer that a grappler has to do something with his position to score... the judging criteria is literally written that way... but Merab was very active from the top.
I figure it about even when O'Malley escaped the 1st TD (with about 1.5 mins left in the round,) but Merab did more than O'Malley after that. I'd say it was close, but not in debate imo.
It would be different had Merab just taken him down without teh striking