The part I'm referring to is at a later point, after the point about SG and LR confirming with KM that they will get the money. I'm specifically focused on the fact that RIvera expressed to police that he didn't understand how KM could have known it was already done.
Initially as people have mentioned, LR says at around 1:25:13 that SG called KM and SG told her "'Everything is, it's done, make sure you have my money, I'm on my way. When we get back to the house....'.... she goes 'don't worry you'll have it tomorrow morning.'" [This is NOT the part I'm referring to.]
Then the investigator asks when he dumped the gun in relation to the phone call and there is an exchange about when the gun was dumped.
And THEN LR says around 1:25:44:
"'Yeah he called her and told her 'it's done, everything's done', I think way before we dumped the gun or after we dumped the gun. But sure, 100%, he called her and said 'hey it's done already.'"
Investigator: "Do you hear her on the other end?"
LR: "Yeah I can hear her, she goes 'ok, I know, alright.'"
Investigator: "'OK I know alright?'"
LR: "I'm like 'yo, how the f--- does she know?' Like 'how would she know if this s--- done?'"
Investigator: "But it's Katie's voice?
LR: "Yeah it's Katie's voice. 100% it's Katie's voice I mean who...He can't call Wendi I don't know her voice, I know Katie's voice....I'm like, 'did she really just call this guy and say "you're done"?' Like where your mind is at."
To me it sounds at the later point in the tape like when KM said "ok I know alright" it wasn't in the context of her communicating "I understand you want your money and you'll have the money" but instead "I know it's done" which it seems would have been what led LR to ask "how the f--- does she know....how would she know if this s---- is done?" Maybe I'm misunderstanding or maybe LR misunderstood at the time. But based on LR's incredulity at her response to SG, it doesn't seem to me that she was referring to the money at that point when she said "OK I know", but to the fact she knew that the job was done. If she was just referring to the money, I don't think he would have wondered "how can she know?" Presumably the investigators will clarify this with LR in future interviews. Speculation, JMO.
I don't know, but if I'm reading this right then LR appears to ask an important question: how could KM already know and how did she find out so quickly?