The articles you link state that they are engaged in speculation. Speculation based on others' speculation does not constitute "evidence," even in this mixed-up post-truth world.
There are a handful of fabs that can make full-frame CMOS image sensors. They are billion dollar investments. The fact that one of these belongs to a company that also has a joint venture with Panasonic does not mean that Leica is a Panasonic company! Frankly, any fab that Leica uses will be linked in to other players in the photo business. That's unavoidable. Only Sony and Canon own their fabs outright, and Sony's fab belongs to a division that is independent of their camera business.
The same phenomenon happens on a much larger scale. Your iPhone contains many components that are made by Samsung! That does not make the iPhone a Samsung product.
The third article you link states that the SL has a log mode, and the GH4 has a log mode, therefore ...?
The author may not be aware that Sony, Canon, Arriflex, etc, also have log modes.
Leica's log mode is reputedly closer to Arri's than to others, and they are both German, so are they the same company? As the article says, it's all speculation.
Not sure what your point is about the Portugal factory. That factory was established in 1973, and Leica does not make a secret of it. You can arrange a visit if you want:
http://www.fdtimes.com/2017/02/22/leica-portugal-tour/