Link Created Service Request from Opportunity to a DCL or Service Request Subtab

Summary:

We have setup Service request as a subtab on opportunity page and set an Object trigger which creates a service request from opportunity. However we are unable to link the newly created service request to a Dynamic choice list field on opportunity page or to Service request subtab on opportunity from which service request is created. Anybody had any success in getting Service request linked to opportunity for Service request created via object trigger or action link.

Content (required):

We are trying below code to create Service request and search for the created SR and link it to Email DCL field. Anybody has any suggestions/solutions to achieve the result.