Simon Simpleton was born in London, England. His mother was Welsh and his father Scottish. When Simon was eight his mother died. When Simon was ten his father married an Irish women and suddenly Simon had an Irish sister. When Simon was twenty four he graduated as a lawyer and took a job in Edinburgh, Scotland. He is now sixty six. Why can he not be buried on the banks of Loch Lomond in his favorite village of Luss, in Bonnie Scotland.

“He was already buried somewhere else.”

The riddle states that Simon is still alive at sixty-six, meaning he hasn't been buried anywhere.

“He doesn't want to be buried there.”

The riddle does not suggest Simon's preference for burial; it explicitly states he cannot be buried there simply because he is alive.

“He wasn't born in Scotland.”

While it is true that Simon was born in London, his birthplace is irrelevant to the question of why he cannot be buried in Scotland; the key issue is his living status.