POP UP Enhancement in FPM

Hello Experts,

                       I have a requirement to throw Custom POP up screen when the user  clicks on Edit or Add button for Medical plans in the benefits enrollment screen. My issue is that i am not able to capture the right event or point where to perform the calls for the pop up, As the requirement is to throw POP-UP for only medical plans. The event that is being called "BEN_EDT" is same for even vision and dental plans as well.

Technical Help :

I did a debug on both the components FPM_GAF_COMPONENT and FPM_LIST_UIBB. As these are standard components the data is handled dynamically and being filled inside standard classes. I found that inside the method CL_FPM_LIST_ASSISTANCE=>DISPATCH_PBO, the data is being filled dynamically. This method is being called inside the FPM_LIST_ASSISTANCE component controller "PROCESS_BEFORE_OUTPUT". I thought of enhancing the method " Dispatch_Pbo"  with an export parameter to capture the data and perform my conditions for POP -Up inside "PROCESS_BEFORE_OUTPUT" but system is not allowing me to  add paramters to the standard method.Please help me,  how would i be able to capture the right event ?  where is the right place to perform this enhancement ?

Debugging Screen :

Data Being Filled in the Standard Class:

Thanks In advance !!,

Vishnu