Requested_for field on both sc_req_item & sc_request populate in workflow

[Lkr]

Hello 

I have a catalog item with a workflow where I have managed to insert a run script thats inserts the custom requested for variable from the catalog item into the requested_for field on sc_request level. However, when I look at the requested item list view, the only variable I can choose in the 'list column view' is another variable that is connected to sc_req_item table and referencing sys_user. I have tried to create another run script that will set the other field with the same requested for input, but I cannot seem to figure out how to 'reach' that field.. I have tried different scripts. 

Any one who knows this issue? I can't seem to find any documentation on why we have these 2 requested_for fields, but as I understand they are not custom made. 
Thanks! Looking forward to get input from someone else.
Let me know if further info is needed. 

Dictionary info for the one that I am able to override: 

Dictionary Info: sc_req_item.request.requested_for

Table
sc_req_item
Field
request
Type
reference
Reference
sc_request
Max Length
32
Attributes
edge_encryption_enabled=true,​encode_utf8=false

Dictionary info for the one that I am NOT able to override: 

Dictionary Info: sc_req_item.requested_for

Table
sc_req_item
Field
requested_for
Type
reference
Reference
sys_user
Max Length
32
Attributes
encode_utf8=false,​no_text_index=true