Very bad service

We had our year end function at mentioned restaurant (?). We (93) employees arrived at 12h30. Waited for more than an hour for our first drinks. Starters was served at about 14h00. (Cold). Main course served at 15h20 in drips and drabs. Also cold. We were booked until 16h00. Left at 16h00 and no desert was served. 27 colleagues didn't receive their food at all. They were still waiting at 17h00. No cutlery or serviettes was given. Until we asked. The noise was horrendous. Couldn't have a conversation with the person sitting next to you. We had to pay upfront for food and drinks. There was only one waiter to serve 93 people. Much later, after requesting, 2 more waiters were assigned. Which obviously wasn't enough.