Only if you make many assumptions. Otherwise, he's wrong. The only
correct answer is "unknown" because of lacking information. The only
way to get off of, "unknown", is to make assumptions, which Cecil
happily did. Therefore, if he's allowed to make assumptions, so are
the rest of us. Which means, the answer is equally, "no".

Either way, he's wrong because he made an assumption or he's wrong
because we are allowed to make assumptions in the other direction,
thusly proving he's wrong.