I was at the convention, things did look tense with Jensen and Danneel but as I understand it from a friend who saw it happen, Creation scolded Danneel after she had signed a few things and told her not to do it because she wasn't a 'contracted' guest.

Jensen apparently didn't know about this when he asked her to sign your friend's script and Danneel just plain didn't know what to do about the situation and ended up coming off looking awkward.

It's a shame it happened that way because it seemed to end up embarrassing everyone involved and creating hard feelings. I'm sorry to hear this happened to your friend.