I thought of that...but didn't feel comfortable doing it with a legal document. There must be a reason they locked it.
Frustrating, and I was so obsessed with finishing in time (found out about the contest late, in a very inopportune time in my life/work schedule) that I didn't even consider that I might not be able to sign the submission form digitally. It would have been helpful to have that defined in the rules of submission.