Funny the Bonnie and Clyde reference... Anyone notice the Facebook picture of the horses? Named Bonnie and Clyde? Also the picture of the couple kissing? Dressed as Bonnie and Clyde? Not really sure if that is who they were dressed as, but that is what popped in my mind. Check it out...
In all seriousness though, I am struggling to completely pass the idea that it was not Tina at the bank. It does look like her. I am in Arizona and it is odd that the story has not been circulated more and more or less swept under the rug. I can-not say that it is unrelated when either case has yet to be solved.
My initial thought was that the son has something to do with it, along with the cousin. That is still my strongest scenario ( almost a tie), followed by Mike, then the whole drug cartel thing, which is completely going down the rabbit hole. It had to start at their home and continue from there. I live about 50 miles from this area and the whole drug thing seems far fetched. Yuma? Perhaps. Maricopa, not so much. I highly doubt this was random...
I believe that someone close to the family or area is responsible. Location of the car, wallet at home, recent arson, money issues... This will not end well. It won't. Not this far along.
As for the PI? Seems like a horrible waste of money. Under resourced, going on the same info we have for the most part.