Hi Tegwyn,
Rather than manually adding each custom parameter to a view, I invite you to instead try our Excel Updater Generator solution, which would let you "point" to the custom form of interest and export a text document that includes a textmode view of all core and custom parameters. With that in hand (and optionally, first deleting all core info other than ID and Name, thereby leaving just the DE: custom data columns of interest), you can then copy and paste it into a new view in Workfront, and viola, export to Excel.
Regards,
Doug