How would you resolve the following situation?

The lunch service has just commenced, it is 12:30pm and there has been a large group of corporate customers from the office tower across the street that has come in without a booking. They are a group of 10 and the manager of the group has said they have a meeting with clients at 1pm so they need their meals quickly, but you have had a staff member call in sick at the last minute so you are short staffed.

Outline the steps you would take including communication techniques you would use and steps for a resolution.