This is faily early in a $30 MTT on Stars. Blinds 25/50.

Pre-flop: (9 players) Hero is Button with
3 folds, MP2 raises to t100, MP3 calls t100 (pot was t175), CO calls t100 (pot was t275), Hero calls t100 (pot was t375), SB calls t75 (pot was t475), BB calls t50 (pot was t550).

Cheap to get in and lots of odds.

Flop: (t600, 6 players)
SB checks, BB checks, MP2 checks, MP3 checks, CO checks, Hero bets t350, 3 folds, MP3 raises to t950, CO folds, Hero raises all-in t2695, MP3 calls t1745 (pot was t4245).

Here's my thought process when it checks to me. I am too vulnerable to check as I could have the best hand here. However, one of the blinds could have a better hand, so I bet to see what happens. IMO, You absolutely cannot rely on a check raise with a board like this if you are MP2, MP3 or CO. What could MP3 have that would justify a raise here? A heart draw? A bluff? Wouldn't anything better than what I've got have to lead? Plus if I am behind, a lot of hands may fold to my show of strength (77, 88, 99, bigger 6's)

Turn: (t5990, 1 player + 1 all-in - Main pot: t5990)


River: (t5990, 1 player + 1 all-in - Main pot: t5990)


Results:
Final pot: t5990
MP3 showed 8s 8d


What do you think of my reasoning? Who's the bigger donk, me or MP3?