I missed something. howcome noone picked her?

Most noms were based on things that had happened in the last 48 hours and Carol wasn't there so escaped their attention.

None if them have any reason to nominate Carol. she makes them laugh and entertains them. Her opinions on all of them are openly displayed, her bitching is always done in a witty way and its mostly done affectionately. The exception to that was Sophie and she's gone.

Carol wasn't immune - I think having been in the other room overnight, they let he off - and they had other fish to fry !

They'll have been thinking about their noms before carol re entered the house so probably had planned what they were going to do.