Yes, there was a fire alarm at the Grand Californian on Friday night. My family was at dinner at Storyteller’s when the alarm sounded, fairly quietly. It took a few minutes before we were asked by restaurant staff to evacuate. We were directed through the lobby and then out the front door and into the outer car area (so the fire trucks could enter the inner area). I couldn’t see completely, but 5 vehicles, including a car or two, sounds reasonable.
We were allowed back in within a few minutes after the fire vehicles arrived. So it was probably either a false alarm or a small fire that was extinguished quickly and just had to be checked to be sure it was out.