So i figured it out...
First of all, i was using the new option in C2 export (cordova), use new intelxdk format.
This was the first big problem.
So i unchecked that.
Next up i removed the official iap plugin.
I removed the phonegap iap plugin but kept the cranberry cordova iap plugin.
I exported to a whole new intelxdk project and instantly intelxdk recognised and imported the plugins.
I build using intel xdk (added nothing manually).
Build went correct.
Uploaded to google developer panel.
Now i can add billing.
So this was +- 7 hours of research with E-bombs exploding in my brain.
But now... im happy again