Shannon,
As far as I know, there is only one elimination on the actual assessment day which is based on your entire performance throughout the day: impressions, measurement of your height and weight, language test and participation in group discussions.
It's really difficult to say why your friend was eliminated and in which part of the assessment day.
In the group discussion it's important to participate nicely and show that you can actually work with others. Don't be too dominative or too submissive. Be ackknowledgeable and understanding towards the other people in your group and do not interupt. It's not actually WHAT you say but HOW you say it, unless you would say anything rude or inappropiate of course.