Pickleball Rules Refresher: More line calls

This rule has become highly contested lately. Here's the scenario: A doubles match is underway, and play is furiously going on between both opponents. The rally has continued furiously, with great drop shots in the NVZ, high base-line lobs, quick shots down the middle of no-man's land, and both teams are doing awesome! THEN... the opponents rip a great shot down your partners side close to the baseline, you preview the trajectory and as it gets close to the ground and your partner is waiting for it to bounce, it looks like it will be out so you call it out, and throw up your hand stating the ball is out. But unbeknownst to you, the ball curves back slightly near your partners court shoes, and even though you have called the ball out, and are looking towards your opponent, the ball hits the court! The ball is in, and your partner decides to play the ball, being the honest person that they are, and sends it back to your opponents.

1. What happens? 
2. What about the call? 
3. Should they have played it?

First of all in IFP rules: 6.D.6. it states, "Don’t call a ball “out” when you are looking across the line unless you can clearly see the space between the line and the ball as it hits. The player’s depth of field judgment, based on the laws of parallax, prevent accurate judgment in these cases.

Further in 6.D.10 it states, "In doubles play, if one player calls the ball “out” and the partner calls it “in,” then doubt exists, and the ball must be declared “in” (except that any player may appeal a call to the referee in an officiated match).

6.D.12. If, while the ball is in the air, a player yells “out,” “no,” “bounce it,” or any other word to communicate to his or her partner that the ball may be out, it shall be considered player communication. If the ball lands in, play will continue. If the out call is made after the ball has hit the playing surface, it shall be considered a line call and play shall stop. (revised April 1, 2011)

Based on these rulings, and how I've been playing those rules I would say my partner was in the best position to make that difficult line call, and if he played it then play should continue. If the opponent got confused between my yelling that it was out, and my partner saying the ball was in and playing the return, and the opponent stops play, then all parties can agree to replay, if not then benefit of the doubt goes to the opponent.

Unless I hear otherwise, and often in a loud gymnasium, it is hard to hear all line calls of our opponents, I will play my returns until play stops completely by my opponent waving their paddle to stop, or my partner yelling stop play, or fault is made.