Why do you need a MAC for CocoonJS? You can use the cloud based compile for the final IPA which isn't a converter. The code is still HTML5 it's just loaded in a focused platform specific accelerated browser (that's cocoonJS, aka a HTML wrapper) which loads your HTML5. If you do need the application security key (apple profile etc..), you can do that without mac too (
For testing you can use the CocoonJS Launcher app which is free, and it's soooo easy to use. Just register and put your code from email into the app when asked, upload your exported zip from C2 to your own url or dropbox and pick that address in the test section of the app.