Considering he has candy as his profile picture and banner on FB along with 12 friends I'd assume its a young kid on the other end so wouldn't pay too much attention to him.
He is basically putting together the wording Thorpe Park used: "We won't reveal all the secrets!" along with when clue seven was first unlocked it didn't show any confirmation of entry so people thought that wasn't the end and there were more clues to solve.
IF there is an 8th clue it may be a puzzle not related to the competition in which people can uncover the opening date of the attraction ahead of a public announcement. Thorpe Park did give me an interesting response earlier in the week saying "that may be revealed sooner than you think..."
As for the competition you are only required to solve the seven clues available to be entered, it'd be a bit misleading to say you were entered if in fact you weren't.