Someone must feel really lucky today. I highly believe the person behind these coins had indeed lost access and found it after 14 years. You can't have this level of self-control to not spend any coin.
I've been seeing this news all over the forum boards, multiple threads in a single board even.
Since we're speculating now: I don't think the keys were lost. As I wrote above (4 years ago), it was worth $30k when it was received. That doesn't sounds like something to lose access to.
More speculation: There's a chance that it's related to:
/index.php?topic=5547249.0Because the timestamp of the OP's last reply to confirm his doubts has a relatively good gap after the 10k BTC transaction's timestamp.
On the very low chance that it's him; he totally messed-up his plan to use coin control.