Did you try with .ipa of the app?
With xcode , product > archive > save as adhoc > export > will give you .ipa of your app.
Then give capability as,
capabilities.setCapability("app", "aa/bb/zzz.ipa");
I don't know will it work or not. Can you plz try it?
And also keep in mind to use iOS 10. version device.
In 9 it does not work.