Hey Denis,
After poking around your sample VPAID, it looks like a an error with the JSON parsing in your VPAID code. Specifically, when it parses the AdParameters:
// Parse the incoming parameters.
this.parameters_ = JSON.parse(creativeData['AdParameters']);
That JSON parser wants all name/values to be surrounded with double quotes. So if I update the AdParameter value in the VAST response to the following, it works:
<AdParameters>
<![CDATA[
]]>
</AdParameters>
So updating your VAST with the above values and/or doing a JSON format check in the VPAID ad code should keep the error away.
Cheers,