I am not 100% sure I understand your ask or where the problem lies, but I do have a question for you that may help you think about this.
You are using a numbered list where you have the display name set to -14 for all list items, why?
Also, you are using list properties, you should avoid doing so and instead create a System module dimensioned by the comp_pro_po_supply list and store these properties in the module. You can later access the properties much easier.
System modules are created to adhere to Best Practice. One type of these system modules is modules to hold list properties instead of actually using list properties. We are moving away from using list properties.
If you haven't yet, please read the Planual as a guide to Best Practice.
Also, this post by @Misbah will give you more details on the how and why we should use System modules for lists.
The source 'Destination Org' is a list property of the 'comp_pro_po_supply" list, however, the target module 'Comp Incoming PR/PO' is using a different list ('svr_pro_po_supply") as its dimension. Since the source and target dimension don't match, your formula won't work unless there is a linkage/relationship between the two.
What is the relationship between the two lists? We can create a list property to establish the mapping of the two lists and then use a lookup formula to populate the line item 'Destination Org (Source)' .