Leaked is not the correct word here. Generally as it's used, it implies some intent to disclose, the information for it's own purposes. You would call a disclosure to the war thunder forums a leak, because the intent was to use that information to win an argument. You wouldn't call Leaving boxes of classified information in a wearhouse where you'd normally read them a leak. (At least not as a verb). Likewise you wouldn't call it a leak if you mistakenly abandoned them in a park.

That said, IIRC For Official Use Only is the lowest level of classification (note not classified) it's not even NOFORN. It's even multiple levels below Sensitive But Unclassified.

So, who cares?

Much more significant is he failed the SCI/full poly... that means you lied about something. Yes I know polys don't work, but the point of the poly is to try to ensure you've disclosed everything that could be used against you, which ideally means no one could flip you or manipulate you. The functional part is to determine if you have anxiety about things you might try to hide, because that fear can be used against you. No fear/anxiety, or nothing you're trying to hide means you're harder to manipulate.

That feels bad even ignoring the whole hostile spys kinda thing.