Linking custom request forms to projects after project has already been created.

Hello! Question on custom forms here - I was testing this all in Sandbox environment, so perhaps this is the issue but here is the scenario:

A team would like to link an existing project through various request queues that succeed it as it goes through the project/product development lifecycle. There are different request custom forms filled out for each phase. I am able to go in to each request and select "Resolved by" and link to that project. But when I go to the Project itself to add that request custom form (in project object format) - the data does not display in the project custom forms section. It all remains blank. Is there a way to fix this or is this a system limitation of Workfront where data can't subsequently flow through if the request isn't "Converted" to a Project directly?

Thank you in advance for any guidance on this.