I read so many articles and watch videos about this case and read this forum from the beginning. I would like to add my two cents to this case.
First of all, I am German and grew up in Germany (West Germany) during late 90's. I took a hard look at Jennifer handwriting of the registration card.
She definitely wrote 148 Rue de la Station ( and not Stehde). Furthermore, we (Germans) usually write street name first but we were taught in school (British English) when writing our address in foreign countries to use number first.
I searched on google map and this address comes up if you input the street name and number:
Rue de la Station 148, 7700 Mouscron, Belgium & Rue de la Station 148, 1200 Woluwe-Saint-Pierre, Belgium. Neither are in Verlaine.
Jennifer supposed to work for a company called Cerbis according to the registration card but that doesn't exist and is not handwritten by her. I feel like the receptionist just wrote what she thought Jennifer said.
There is an air defense system name Cerebus which are made by the Belgium Government to protect from incoming drones, etc.
If the BL country code stands for ( Belgium - Luxembourg) then there is also a street name with that number
148 rue de la station, 1721 dommeldange luxembourg and company called Cerebus Capital management
Cerberus Capital Luxembourg S.à r.l.. There is also a zip code 7568 in Mersh, Luxembourg.
In conclusion, I really think she lied about where she lives. That street name and number is very common in Belgium and Luxembourg. She mixed some Belgium & Luxembourg street name & number and Luxembourg zip code in there with wrong Belgium city lol. Jennifer was trolling with the BL country code if it really stand for Belgium & Luxembourg because her address is made up by locations from those two countries.
I think Jennifer might not be from Germany but from Luxembourg since they also speak German. It was said she spoke an East German accent that could also be confused for someone speaking German and living in Luxembourg. Or she is from East German and knows Belgium and Luxembourg area very well.
If you look at her watch and gun, which are used in military/police agencies, I think she most likely was a spy. Why would a high end escort bother with concealing the gun's serial number and her address?!
The hotel she stayed at held very important meetings with high officials from different countries to discuss several major world issues including the Israeli/Palestine conflict.
The German Democratic Republic (GDR) was heavily involved with the Israeli/Plestine conflict and opposed the Israeli regime. Jennifer might have attended those meetings with high level officials discussing that conflict or was there to gather intelligence about these meetings.
At the end, I think Jennifer got taking out by that neighbor Mr F who stayed across her door. He basically slipped up when he told a reporter that staff told him Jennifer was dead and ask him questions about it. However, he left a day before she was found dead and he should not have known that.
Was Mister F a Mossad agent or a guy she had sex with or he tried to force himself on her and she refused?