I'm not sure what you're looking to achieve is possible at all in the current HTML5/C2 restrictions.
If you want minigames "embed" inside an app, I'm afraid you'll have to redo/reexport the app so that it does contain the minigames, this way everything is inside a single apk file.
Accessing "local" games is prevented by browsers (the screenshot you displayed) for security and compatibility reasons.
Apart from an iFrame and possibly internet connection, I'm really not sure it is at all possible to access/provide those files/games.