Yes, again, if he signed by that Friday, HE HAS TO SUBMIT IT WITHIN SEVEN DAYS. I'm not yelling at you, you're asking in good faith, I just wanted to emphasize that part!
Yes, he would have had to submit the LOI. And if he did, then whatever school he signed with COULD THEN COMMENT ON HIM. And it would be advantageous to do so TO PROHIBIT TAMPERING with a signed recruit.
I mean, I understand the "building suspense" stuff, but signing (and submitting) an LOI in secret is just about the worst and most legally misleading way of doing so. And might even constitute recruiting violations, in that other schools are then pursuing communication that is otherwise prohibited.