There's no way to modify that setting for paused jobs (you can modify the print ticket settings but that's about it).
I would suggest making a duplicate workflow and changing that one setting (make sure you make a new preset otherwise changes to the preset will change both workflows).
If there's a request to remove the marks you can then cancel the job and resubmit it to the other workflow.
Sometimes we get special requests to remove the trim marks off of one of the documents we are printing. Is there a way of modifying the ticket when I have already submitted it into the Active Jobs screen under jobs status?
Scott