generally wont but , sap does not handle all ui components in the same way. i am not sure but what i could see in the set data method is, they are using one static method which is getting the instance of old genil component class.
lr_case_genil = cl_crm_cmg_il=>get_case_bol( ).
so redefine the method set data and call that static method with your new copy genil class.
lr_case_genil =(your new genil class )=>get_case_bol( ).
if it does not work, then redefine the get_case_bol method and change the return parameter type to your new genil class ( it is returning old genil class reference ).
i hope it works for your.