Dynamically pick a child slatebrush? Need help just condensing it down

Hey,

I cant for the life of me figure out how to link these achievment array and slatebrush so I can change the overlayed image.

if the number 4 exists in the array. change index 0 in the slate brush to a different image,
if number 5 exists in the array, chage index 1 in the slate brush to a different image.
The numbers in achievment array might be collected randomly.

if I use the contains node it changes every image. not just index 0.

so in my head I need, if achievement array contains number 4, then append slatebrush array index 0 from a null image, to a crossout image.

I Just dont know enough nodes to figure it out. Thanks for reading.


Some attempts

I feel so close. this changes all of them, not just index 0

Holy // this actually works…Its been 4 days at this, I could jump out my skin.

This works. I just need to figure out how to condense it.