Hello,
Could you try proxy recording?
http://vugenhelp.saas.hpe.com/en/12.53/help/WebHelp/Content/VuGen/c_ProxyRecording.htm
And we can also generate script by analyzing captured traffic file:
http://lrhelp.saas.hpe.com/en/12.53/help/WebHelp/Content/VuGen/How_to_Analyze_Traffic_file.htm
Regards,
Bingle(LoadRunner R&D)