Set Replacement SO on RA

When I save a Sales Order that is a replacement for a Return Auth, I have a custom field on the SO that links it to the RA. When I save the SO, I'd like to browse back to the RA and add the SO# in custom field I have setup over there.

My workflow is setup to run after record submit. I'm using a Go To Record action, which works correctly as I'm redirected to the expected RA. Under the "Fields" section I'm choosing the field on my RA, and setting the value with a formula of {id} as transaction or document # is not available in the "Value Field" column. When I save my SO, however, the system takes me to the RA, but the field is not populated. When I check my logs, I can see the internal ID of the SO is captured n the workflow, but it doesn't