It sounds like you have entitlement issues. If you embed a executable within a sandboxed app it must have the
com.apple.security.inheritentitlements, and only those entitlements . You can learn more about this in the the [Enabling App Sandbox Inheritance][docs] section of the Entitlement Key Reference.
I recommend that you dump the entitlements of your built binary to see what’s what. You can learn more about that in Technote 2415 Entitlements Troubleshooting.
Share and Enjoy
Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware
let myEmail = "eskimo" + "1" + "@apple.com"
 The other options is to have no entitlements, which is a compatibility path that gives you the same behaviour, but my experience is that this is frowned upon by the App Store submission machinery.