Adding a half hour to that timeline makes no difference.
Can you explain how Sheriff Reader,who responds after the murders were called in to 911, (he wasn't a first responder at the scenes) would be able to plant DNA at the crime scenes? Are you assuming he carried around some samples of Wagner family members DNA to plant there? Alternatively, he would have to observe the crime scenes, decide to frame the Wagners (why?) and would have to leave the crime scenes, with hundreds of first responders around, multiple helicopters overhead and dozens of news cameras at every intersection nearby, and drive over to the Wagners farm on Peterson Rd. to somehow get into their home, while they were there and take some DNA samples.
Keep in mind, all the evidence at the crime scenes was retrieved by BCI and their crime scene experts who then took it to the BCI labs for examination.
If your theory is that Sheriff Reader somehow planted evidence at the crime scene while BCI was processing it, why would he wait for over a year after the murders before pursuing them?
JMO
ETA: See timeline on p 1 of this thread for the names of the first responders to the crime scene.
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