As per wiki, we need to pass ControlLoopElementDefinition (Or in Tosca terms ToscaNodeTemplate) alone instead of passing complete ToscaServiceTemplate to every ControlLoopElement.
But, When it comes to Policy ControlLoopElement, "policies" and "policy-types" doesnot reside under ToscaNodeTemplate, They are either siblings to ToscaNodeTemplate or siblings of ToscaTopologyTemplate.
For this reason, As a stop gap solution, to unblock Policy Participant work that is being done in https://jira.onap.org/browse/POLICY-3508 I had to keep the interface as it is, and get the ToscaServiceTemplate with a new API below.
ToscaServiceTemplate controlLoopDefinition = intermediaryApi.getToscaServiceTemplate();

This needs a discussion to either reorganize ToscaServiceTemplate Or update the interfaces accordingly.