Haven't tried this before but is it possible to use e-credits from multiple passengers to book a new reservation for these passengers on the same reservation?

I.e. I booked a ticket for me and my spouse on the same reservation (same PNR). Trip was canceled. The e-credit for my ticket is in my DL wallet. The e-credit for my spouse is in her DL wallet. Obviously when I login to DL.com, I can only see/access my e-credits. My question is: Can I book a new reservation where we will both be on the same reservation (PNR) using my e-credit towards my ticket cost and her e-credit towards her ticket cost and is that possible to do online without calling? Can I add her e-credit during the check-out process by pulling he 006XXXXXXXXXX. number? Or is this something I would have to call in and have an agent do by providing the e-credit info for my spouse to have the e-credit applied that way towards her airfare to then get us on the same reservation?