wondering about line 15 (RunningMode::pathtoinstalledpackages) logs the path of the MSFS2020 installed on this system.
Not a problem, it's just a log message.
After applying the workaround with the 32-bit in the XML the menuentries are shown.
Hoping this helps for further investigations.
Yes, it helps a lot, because I can see why it doesn't load. Can you please check the Digital Signature for this file ?
Addon Manager\couatl64\couatl64_P3D.exe
Right-click on it, select Properties->Digital signature, and check if it's valid, and its date/time.