Originally Posted by
Ametrine
In the English version, Lyse specifically mentioned they didn't publicly reveal Zeno's gravesight, implied to keep the Ala Mhigan people from doing something regrettable to the corpse.
So, the whole thing is super sketchy from the start. Unlike with most other actually dead characters, we never had our hands on the body. He coughs blood, delights in the fight, cuts his neck, and "passed out."
So, I'm thinking someone, a double-agent Ala Mhigan perhaps, stole away the real Zenos instead of burying him. It's probably a different body in that grave, and keeping the site secret prevents the news of the switch from coming to light.