WOW! You are absolutely correct, this is NOT Misty's voice! I will admit I do not know exactly what is being said in the background with Ron and Misty and possible even a third voice (other than the female on the phone talking with the dispatcher) but clearly there is at least one female voice other than Misty's on this tape...and clearly she says "but that's my last name."
I listened to this four times and there is no doubt about it, there is another female voice on the tape and I am thinking there could even be two others besides Misty's, one talking on the phone at that point and another that doesn't sound like Misty in the background. I could hear Misty kind of sobbing or sniffling, but the voice on the phone wasn't, and I hear yet another female in the background that isn't sobbing/sniffling and doesn't sound like Misty.
Am I the only one hearing that other voice?
I think that 911 recording was redacted practically to smithereens and there was a lot more going on there than what's left of the tape indicates.
Lone, you really have a good ear!