Well I'd be prepared to eat my hat if the lameness wasn't due to an abscess that exited at the sole and leaked or at the very least caused some damage at the coronet, which has since grown down. The line on the outside is clear and it matches positioning of the hole at the edge of the sole at the bottom. Soles grow forward from the heel so it looks further forward now, but it wasn't at the time it happened.
I think you can probably forget about the lameness in that foot at that time being anything that will cause any problems in future.