var InstanceObj = new createjs.Text(InstanceTxt, "12px Helvetica Light", "#000000");
You could change it to:
var InstanceObj = new createjs.Text(InstanceTxt, "12px Helvetica Light, Arial, sans-serif", "#000000");
In some versions of Indesign (Japanese, Chinese, etc), there's option to create composite fonts, where you can define different fronts for different sets of languages. It could help you.
You can download those versions by changing the language in your CC preferences (the UI will still be in English as long as your system display language is English)
This method could also help: Change default font for fallback in PDF editing and Add Text
He didn't need a composite multi-language font, he needed fallback fonts if the preferred font wasn't installed on the user's system. That's a completely different problem.