Hello Bill,
I do not believe this is possible. The requests that were started prior are still using the older version of the Composer solution, so it would still not see those fields as promoted to SharePoint.
You could could manually update the SharePoint list to have the values, depending on the data and if you have the proper permissions. Doing this to the SharePoint data will not impact the request forms.
------------------------------
Scott Gorski
General Mills | Data Analyst
------------------------------