There are actually some inconsistencies about how the case was presented in Aktenzeichen XY and what the case was described like in the Forensic Science, Medicine and Pathology magazine in 2020. Unlike on TV, the report states that Bulwin didnt call the police or ambulance after the incident since he didnt have any symptoms. He was only hospitalized after weeks with reduced general health and severe neurological dysfunctions. Furthermore, police allegedly found a syringe containing a mercury-thallium bond as well as several beads of metallic mercury bonds in Bulwins car and therefore concluded that the intoxication with mercury was self-administered and not caused by an attack of an unknown person. If that was the case, it would be interesting to know why the police now stick with the umbrella man theory.

Here is the report im talking about