Hello Om,
the method SEARCH_PARTNERS of the mentioned BAdI Implementation won't be called, if method IF_EX_CRM_BUPA_IL_SEARCH_EXT~SEARCH_CRITERIA_INITIAL is returning parameter CV_IS_NOT_INITIAL with value ABAP_FALSE.
However the BadI implementation allows custom search criteria. In your case you can simply add further attributes to the context node. Therefore change method GET_TABLE_LINE_SAMPLE of context node RESULT (view BP_CONT_SEARCH/SearchResult ) and create corresponding GETTTER methods. Maybe you have to handle a MIXED node.
Please check also https://scn.sap.com/thread/2104183
Best regards,
Daniel