For Lufthansa cabin crew members the same since last update to 3.7.3., no Lufthansa uniform, but generic with red scarf, no badge on uniform. PMDG 737-700. Aircraft config ICAO code is DLH.
I fixed my above topic by without the simulator running going into the D:\msfs\community\pmdg-aircraft-737-liveries directory which is my community directory on drive D: and the pmdg 737 liveries directory in there. I then placed the "mslayoutconfigurator.exe" file into that directory (downloaded from Github) and dropped the layout.json file onto the "mslayoutconfigurator.exe" with the mouse to update by this action the layout.json file.
After that having started MSFS2020 again and loading the PMDG-700 Lufthansa Livery the correct uniform showed up.
All working now.