Preflop:
-Moga raises with A9o-standard
-Negs calls wit K10s-standard hand to defend with
Flop: 4H-QH-AC
-Negs checks
-Moga bets out a small 30K into the pot which might've worked if Negs had a hand like 67s or J9s.
-Negs check/raises to 85K. This is a great check raise if he thinks Moga has a hand like 1010 or JJ. This raise can either win him the pot there or he can hit on the turn. Also, very likely Negs lets this hand go if Moga 3bets here.
-Moga calls and Negs has to put him on at least an A. It's very unlikely Moga is calling with just a Q.
Turn: [4H-QH-AC]3H
-Negs checks
-Moga checks; very good pot control here. If he bets out, there's a good chance Negs could check/raise again. He is drawing to the nut flush, but if he is behind a better A or a made flush, he'd rather just try and take the free card.
River: [4H-QH-AC-3H]7S
-Negs has to bet here because his hand has no showdown value. If he checks, there is no way Moga betting for value and will check behind. So, a bet here is the only way he can win the pot. The way Moga played the hand, Negs is probably confident Moga has a weak Ace. It's also unlikely that Moga is slow playing a hand like 44 because he lost a lot of value by checking behind on the turn.
So, the only way for Negs to win is to go for a pot-sized bet, which could either mean: A) he has it and is trying to get paid off or B) it's just a
bluff. Keep in mind, he's not going for a value bet of 1/3-1/2 pot because that's even easier for Moga to call and see the hand. The pot-sized bet is the only way Negs can apply maximum pressure, without over-betting.
-Moga probably should've called there. Negs isn't showing a lot of
hands that beat him in that situation, especially the way the hand played out. Small check/raise on the flop, check turn, pot-sized bet on the river when a 7s comes out? It doesn't make a lot of sense. If Negs did have a hand like AQ/AK, you could expect a 3bet preflop. And if he had a hand like A4 or 44, he very likely would've bet the turn as well. It's unlikely he's playing a hand like 25(even suited) or Q4.
So, Negs is either representing a made flush, a weaker pair like Q10, or air, and Moga beats 2/3. Easy call.