Advanced Slicer help!

Hi, I have data that I want a unique solution to, and it is quite a challenge. Here is the dilemma:

I need to filter out the "Duplicate" ID values to only show a consolidated view as in below;

I need to remove the "Column for slicer" column in the end to show ID and key ONLY.

I cannot simply put "Column for Slicer" in the slicer of my visualization because it would not properly function to display ID of "2" when selecting filter A.

ID    Key        Column For Slicer

1         A                  A

2         A+B             A

2         A+B             B

3          B                  B

4          C                 C

Can anyone help with this?