If a token goes to the graveyard it changes zones and once it's in the grave, then it ceases to exist. Wouldn't 'ceases to exist' imply the token was in the grave and left?
It's a stretch but "leave your graveyard" is strange wording. I can see how this would create infinite loops if you had something like Heartless Summoning in play which again makes me think this can't work with tokens hitting the grave.
110.5f A token that’s in a zone other than the battlefield ceases to exist. This is a state-based action; see rule 704. (Note that if a token changes zones, applicable triggered abilities will trigger before the token ceases to exist.)
704.5d If a token is in a zone other than the battlefield, it ceases to exist.