Checking logs, I also see this which seems like it might be relevant:
<rdar://problem/11489077> A sandboxed application with pid 816, '"MyApp.app"', checked in with appleeventsd, but its code signature could not be read and validated by appleeventsd, and so it cannot receive AppleEvents targeted by name, bundle id, or signature. Install the application in /Applications/ or some other world readable location to resolve this issue. Error=ERROR: #100013 { "NSDescription"="SecCodeCopySigningInformation() returned 100013, -." }This happens when I download my notarized app and launch it. If I validate the signature for the downloaded app, it does validate, so I’m not quite sure what the problem is. (This is in Catalina dev beta 5).
I wonder what “checked in with appleeventsd” means?