Discovered the problem. This was more of an exercise in debugging and understanding the difference between testing with livereload vs testing the app untethered.
The problem was a javascript library directory name that was some for reason was not capitalized under root www/lib but capitalized in the platform www/lib.
I am guessing livereload was loading the resources from the root directory and therefore worked correctly whereas in the untethered mode, it was loading it from Myapp.app/www/lib directory
Since I was not seeing any errors in Xcode, I used Safari’s Develop to access the devices’ browser. On the first load I didn’t see any errors, but by reloading the resources, I saw the error message.
Putting it out here, in case you find yourself stuck with a similar, odd issue.