The Killer must have acted alone

There are several indications that the killer acted alone.

Frauke's corpse has not been buried or made disappear in a "professional" either labor-intensve  or power-intensive way.
He just carried the body 30 feet away from the street. Then he didn't bury her, but placed only leaves and twigs on it. Almost like a child would do.
By the way. Have you talked to the guys from the Forensics?

What the phone calls and text messages can tell us.

The first real call came at night 44 hours after she disappeared.
And it was not a real call, because Frauke didn't take questions. Just hung up.
If this was a recording of Frauke, it had been made during that day.
Chris could not tell if she was in a room during this call or not. This could be caused by the substandard recording device that was used.
This call was the only call from this cell tower in Sennelager.
Why did he not bring her with him in the car like he did later, but only a recording? It could be, that this was the place where either he, his wife and kids, his mom and dad or his boss lives, but neither one of the latter had any clue what's going on and the kidnapper/killer wanted to keep it that way. 

The first text message

After the funeral months later the state police  however came to the conclusion that the crime scene must have been somehow close to where the first text message had been sent from. Could be, but there are doubts to it.
The witnesses and profilers came to that conclusion because the text message sounded normal and that it therefore had been sent voluntarily by Frauke. As I said it could be, but how likely is it? Frauke was shy and now she drives around with someone for two hours, out of town, and sends a text message announcing to come home later? Very unlikely. What's more likely is that Frauke had already passed out (on chloroform or k.o. drops), the kidnapper/killer parked his car in a rural area and browsed through her cellphone contacts, especially her sent messages folder.
Then he only needs to copy and paste, by hand of course, and press send. His approach could be helpful in building up his profile later on.

The reason for the calls

I know afterwards it's easy to bash the police for not acting appropriate at the time. And hell they didn't. Didn't tap a single phone, made no recordings of the calls. But what we know now, was not known back then. And the whole thing was over within a few days.
What we know now: The reason for the calls. Their only purpose from the beginning was to buy the kidnapper/killer some time. Frauke probably didn't talk the kidnapper into it to buy herself time to stay alive. It was the kidnapper's idea/plan. So now he sent the text message to Frauke's closest contact. What's next? It could be that he abused her in Nieheim. After that, he drives back to Paderborn.
and brings Frauke in a prepared basement, maybe it's his own, or it belongs to his family or friends.

Frauke awakes

It's perhaps around 1 P.M. on Wednesday, when Frauke awakes. Her hands and feet are tied up, her mouth duct taped. Maybe she is even blindfolded. She is in a room and she is alone. The room could look like the example photo on the left. It could be more comfortable or even less. Hours pass by.
Around 5 P.M. she hears a key being inserted in a lock. It is the kidnapper/killer. He brings her water (drugs) and some food. Then he abuses her again.
After that he leaves.
The same procedure on the next day. He brings her water and food, abuses her.
After that he wants her to say 3 sentences while he is recording it:
"Hello Christos, I wanted to say that I am fine and that I will be home soon. Tell mom and dad and the others."
Takeaways for the profile: He possibly looked up Chris in the phone book and came up with the name "Christos". He has written down the three lines, she only has to read them in the right manner 2, 3, maybe 4 times. He wants to keep control.
At around 8 to 9 P.M. he leaves Frauke alone again. She probably passed out again shortly after.

The kidnapper's daily routine

It has to be assumed that the kidnapper had a very tight schedule at least during the week. This is because the calls were always made outside the regular working hours. Even on Sunday he had no time to call before after 11 P.M.. Of course this could have been decided by him voluntarily. Or the reason was not to be seen on the streets with a hostage on his backseats. Since we decided, that the location of the kidnapper's home and the place where Frauke was held were both in the Paderborn area, maybe were even in the same place, there has to come a question to your mind. What does he do with all of his time, if he's not driving around for hours to fool our genius police officers? Work? Definitely a YES. Wife and kids? Probably a YES.
What job might he be good at? We have to leave that open until we have his profile later on.
And the family thing? There is a certain probability that he, his wife or ex-wife, or his mom or dad live in the Sennelager area. That's from where he calls Chris late that day and plays his recording. Ok. Now you can begin to create a first draft of the kidnapper's profile.

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