I just read this thread from beginning to end, and wow. It's rare that we have the perspective of someone so close to the victim, so thank you CombatMedic for sharing what you have and what you can. I can imagine it's frustrating and heartbreaking to go through the loss of a loved one AND then deal with the innuendo, accusations, and all the rest that goes with a homicide investigation. So please take what I say in the spirit it is intended. I don't disbelieve your experiences with Nikki, but I do question your interpretation that the logical conclusion is that Franz is responsible. But again - we do not have the information that you have, that I hope LE has, only what has been reported in mainstream media, which as we know well has it's own agenda in presenting a good story.
So personally, I have a very hard time making the long leap from what we know to Franz being the perpetrator. Perhaps it's my own lack of imagination, or the rarity of a father killing a grown daughter (are there other examples of this actually occurring?), but I just can't get to a strong enough motive here. The only thing I can think of is past abuse (sexual or violent) that was going to somehow come to light, and there is no indication of that. I read the interview with Franz, and chalked his somewhat abrupt answers up to his not speaking English as a native language and general German-ness, which could also speak to his intolerance of Nikki's feelings. He probably has learned how to just get over things, if he was in Vietnam. I'm just struggling with this but I know I don't have the full picture either.
If it wasn't for what police said about Alexandra knowing her killer, I would be much more inclined to believe random thrill kill - but I suppose a stalker in the neighborhood is still possible, she could know them after all if she was a regular jogger. A stalker though usually has a sexual motive/assault (ie. Katrina Vetrano and Vanessa Marcotte) and even without a SA, it is usually a much more personal type of kill. After the outcome of the Michele Roode-Boyd case, I'm more cautious about jumping to the "ex-boyfriend or ex-husband did it" and remain open to all possibilities. And as LE said, everyone is still a suspect. Regardless, I am interested in the truth and justice for Alex, that is all.