Hi Priya,
redefine OP_Default of the your ZL_ICCMP_BT_INRLASTHIST_IMPL class and get the parent entity of the lr_order and pass to lr_data_collection.
DATA : lr_entity TYPE REF TO cl_crm_bol_entity.
lr_cucobt ?= me->get_custom_controller( controller_id = if_iccmp_global_controller_con=>cucobt ).
IF lv_object_type_s <> 'BUS2000111'.
lr_order ?= ir_entity.
IF lr_order IS BOUND.
IF lr_order->get_name( ) = 'BTAdminH'. "#EC NOTEXT
lr_order = lr_order->get_parent( ).
ENDIF.
IF lr_order->get_name( ) = 'BTOrder'. "#EC NOTEXT
lr_order ?= lr_order->get_root( ).
ENDIF.
ENDIF.
lr_entity ?= lr_order->get_parent( ).
lr_data_collection = lr_cucobt->get_descriptor_object( ir_entity = lr_entity
iv_component = 'ICCMP_BT_IRHIST' ).
Cheers 
Sumeet