Our bank allows customers to submit stop payment requests through digital banking. Before they finalize the submission, we indicate that there will be a charge and the customer should print the confirmation screen, sign and return it to the bank. If they do not do this, then it informs them that the stop payment request will be deleted after 14 days.

We are treating it like a verbal request. And, it is a really clunky process for the customer.

Since the customer has to authenticate before entering digital banking (DB), if we were to save the request from DB, can we treat it as a signed request due to the authentication that had to happen?

Silly question, but in a "smart phone age", how are your customers printing and signing anything?

Why not use DocuSign or something similar?

I hate to take this path but I think this really is a question your bank's legal counsel needs to be providing you guidance with. You should not build a process that is not aligned with your own deposit account agreement.