Old age. For the time Link is a child he could not walk well. So probably in those 7 years he felt ill and died. That illness probably was from a fall he could not walk well so it would not be a surprise if he had a fall. He felled ill because of that and along his old age he went bye-bye
The little boy got old enough that Dampe took him under a tombstone to race him claiming he was "pretty fast". They got so caught up trying to beat the other, they both fell off the cliff before they made it to the finish. Dampe decided to stay under the tombstone as a ghost while the little boy was like "♥♥♥♥♥♥ it" and went off to make let's play videos of OoT on youtube.
Well let's do some basic analysis.
Here's a pic of the bloke: We can see that he's at the least 28 years old. He's bald and has a broken body. This could imply that he's actually much older than just 28.
two timelines right? One where Link prevents the events of OOT by getting ganny executed, and the other where he goes through the 7 years frozen and then in a matter of months to years finishes off ganny atop the castle of evil 666.
Prevention Timeline: I'm not sure if he dies here but if it was a death it would have been from old age or an accident.
Full event Timeline: He would have likely died of old age, as I don't think Kak village was attacked by evil forces. If not, it's most probable that he was murdered.