We were on the Koningsdam ten days ago.   You had to watch the video in your cabin that dealt with how to put on the life vest, etc.   We had a two hour window to report in at our muster station so that the crew member could scan your cabin card to ensure that you made an appearance.  There was no need to bring the life vest to the muster station, just your cabin card to verify that you actually made it to the muster station.