When an opponent makes a binding out of turn action, what are the rules and what is the best play here?

8 handed cash game

$1/$2

Hero has $450 behind

CO calls with $300 behind

Button calls with $250 behind

3 to the flop

Pot: $39

Flop:

Kd9c7d

Checks around

Turn

9h

Hero checks against two super nits

CO bets $20

Button folds

Hero calls

Since I slow played my trips, I will continue my line with a call

River 4c

CO announced "all in" out of turn

Dealer corrects and says CO's action is binding

Hero tanks then decides to check

CO checks behind...what the heck?!

Dealer calls floor and floor rules CO is binding all in...

Hero now knows CO likely has a worse hand and insta calls

Question: if I had bet the river, or moved all in as a bet...would this have relieved CO of verbally binding play?

He definitely got a read off of me by announcing out of turn, since I wasn't sure whether I should bet or check, or what hands he would move all in with...

Pat