There could be some more nuance to it but I'll try to answer. If they never got to dinner, it could be that they didn't progress far enough into their meal to reach dinner. For example before dinner you might eat appetizers. If the power goes out at the restaurant while you're eating your appetizer, you may not end up being able to receive dinner after. Therefore, you didn't get to/end up at dinner. Another situation would be if you missed your reservations altogether and didn't end up arriving at the place you were going to have dinner.