nashwaak I didn't see anywhere in your post that you installed the Sonoma-specific build, which is why I mentioned it.
On the downloads page you can see there's a generic installer which will install the correct build for you but there are also version-specific installers below.

The version I linked above is this: https://cdn.kagi.com/downloads/14_0/Orion.dmg
It's different from the OrionInstaller.dmg at the top of the list. I just thought that might be worth a try. You can try updating and overwriting the existing installed version with the 14_0 one there.
If you ever tried to install Orion RC, that is not going to install over top of your main Orion app. It's treated as a separate app.

Just throwing some ideas around for you. Not speaking on behalf of the Orion team.