Every single person who was in that house on 12/23 has been questioned and DNA-sampled. They are ALL known to LE. *None* were under the umbrella of suspicion except the immediate family, because they could never be cleared.
The only reason we can't say the other party attendees have ALL been cleared is because no one has been cleared in the murder case - with the exception of Burke Ramsey. Maybe Fleet White, but the wording was murky. He requested it of LE, who said it didn't matter because if he came under suspicion he would be "uncleared."
Ok......how about he snuck in one of the entrances during the party? Poked around and if seen, everyone just assumed he was a guest?
I'm reaching....I know!