You can’t create array columns like that in Glide Tables. You can only do it in google sheets. What I would try is to create a template column to join the two image columns with a comma separating them. Then create a Split Text column that splits on that comma and then creates an array.
A multiple relation with a lookup also works as it returns an array, but your data would need to be structured in rows instead of columns. I would try my first suggestion.