The 3rd party software developers aren’t providing any input for their software? What is their response about your problem? Are they working on it? Are they using exe.xml when running MSFS? If yes, then they should provide information about their exe.xml. If no, then maybe their app isn’t designed to work with exe.xml.
Realistically there is no way that MSFS could test and verify EVERY 3rd party app works with exe.xml.
I have been using exe.xml to start two software apps (not any of the apps documented above) for months without issues.