You have submitted your support inquiry for Kendo UI Professional under the Telerik AppBuilder product. I am afraid that AppBuilder forums does not include support for the product you are using and we cannot provide a resolution for your technical question. That is why I'd suggest that you consult the Kendo UI forums
or the referenced there community resources. Also, if you company holds a license for Kendo UI professional, please, contact the license holder to submit a support ticket for the appropriate product.
On a side note, I noticed that the web services should be reached only over HTTPS. Also, it does return the response in XML format. Given that you need to adjust the data source configuration and the web service to communicate better with each other.
Perhaps the Kendo UI resources available in this repository
will be helpful to align your service configuration and the data source. In this demo
you can see how the data source can be bound to an XML.