It Just Takes a Phone Call
At first glance here, I’m on the restaurant owner’s side. His delivery driver has gotten into an accident, and depending on the severity of the accident, they may have had to send out a new driver, or at least, the original driver would have had to stick around and deal with his accident before he could finish his route.

The more I think about it, though, the more I’m on the customer’s side. Getting in an accident is a very good reason for your food to be late, but the delivery driver had this guy’s contact information, I would imagine. To not communicate that you are not delivering on the service you promised—at least, not in the time agreed on—isn’t a great move.