Make invoice header field mandatory based on invoice source

Summary: We were successfully able to make the Requestor field mandatory on the invoice header in the create invoice form. But, this also seems to make the field mandatory now when the business team goes in on a non-mandatory invoice. Is there a way to say only make field mandatory if invoice source is 'manual', 'spreadsheet', etc?

Content (please ensure you mask any confidential information): Payable Invoice Creation

Version (include the version you are using, if applicable): 24C

Code Snippet (add any code snippets that support your topic, if applicable): N/A