No, you cannot. It must be on Delta ticket stock to be eligible for the upgrade. There is no way around that, and DL won't take over a VA ticket. Plus, so many DMs already waitlisting on Delta tickets for this route, it's not like they'll have empty seats at the gate to make an exception.

By the way, here is the entire area that you copied/pasted earlier, which references Ticket Eligibility just three bullet points below the one you quoted. It then goes on to say that they must be upgrade-eligible tickets; VA ticket stock is not upgrade-eligible on Delta.