New on this thread - just a couple of thoughts.
I am confused about Cefuroxim (the antibiotics Lars had to take), because - in contrary to what's stated in the interview - it is NOT banned in Germany. It has never been banned, to this day ever, actually. It runs under other names, like Zinnat and Curocef, but it's the same as this Cef500 and is used widely. It was also used in 2014, when this young man disappeared. Why do media people tell it is/was banned? This is not true. Are there also other mistakes in the interview?
I don't see anything fishy about this medicament anyway. It's just a simple antibiotics. I've taken it several times myself. I'm also a medical professional, and while, according to studies, antibiotics induced psychosis clearly exists, it mostly happens to patients with some prerequisite conditions, like elderly, or with bad kidney function, etc. I have never seen one single such case during my ten years of hospital experience, tbh.
Head injury could be possible - if a smaller vein gets ruptured, it can take some time until symptomes of the growing intracranial pressure set in. The person can look fine for a day with nothing more but a slowly intensifying headache, later some nausea and differing pupils. But the time frame doesn't fit with this theory very well, I think. Concussions can also cause weird behavior and there is a wider time frame for it. More possible, imo.
About the organ trafficking theory from the viewpoint of a medical professional from a similar ex-Socialist country: just no. Random laryngologists in random hospitals aren't involved in organ trafficking, even in the deepest of Balkan. They do not have ready-made boxes of antibiotics that contain something else, just in case a random German tourist, looking perfectly suited for potential illegal organ trafficking purposes, miraculously walks in. They just don't. Hospitals and doctors are just like everywhere else in the world: hospitals and doctors. No exotic mystery organ maffia here.
Also, people clearly have no idea how difficult organ transplantation actually is, how many medically trained people are involved in just taking those organs out. There is full staff from three-four different teams from different hospitals, standing in the OR waiting, ready to fly away with the different organs to their different bases where at the same time other full OR teams are waiting with the recipients already on the table sleeping. Even if the only organ suitable for actual donation turns out to be just one cornea at the end, the whole business is on with all the people all the time. People also clearly have no idea how difficult it is to keep a potential donor's body alive prior/during and the organ after the operation, and how extremely complex the process of finding recipients that match your organs, actually is. Usually every organ goes to another recipient. Nobody receives two kidneys - two different people receive one-one kidney at the same time. It is a very, very complicated and meticulously planned process, involving a huge amount of medically trained personal. It is definitely NOT done by random ear-nose and throat doctors, with the help of fake antibiotics. Eurotransplant or its equivalents in countries not included exist for a reason. Even in Bulgaria.
At this point I cannot even imagine what happened to this young man, but for me two things are clear: nobody gave him false medication and nobody wanted to kidnap him for his kidneys in the Kolor Hotel. They very likely tried to scam his credit card, that's a typical Eastern European crime, maybe they even tried to pickpocket him, but that's all I can imagine. I guess he was scared because for the first time in his West European life he got exposed to the Eastern European reality and because he was alone in that strange new world, he got a bit paranoid about it (paranoid not in the medical sense of the word, of course). That Kolor Hotel doesn't even look shady or scary to me, just normal. I'd totally sleep there and I'm a woman. It's definitely much less sophisticated than the tourist hotels in the Golden Beach area Lars spent the week previous to his disappearence, but that's all.
I'm very sorry for his mother, this not knowing anything since years must be excrutiating.
ETA: since I'm not verified as a medical professional, this is all to be taken as a personal opinion, based on personal experiences.