The text on the lighter originally came from the Chrono Cross instruction booklet, so it's not a random blurb.
In any case, Masato Kato never had to "confirm" that the planet was the Entity, since the Japanese version of CT was pretty much clear about it and there never was any mystery to begin with. Compare with Janus: do you need Kato to confirm that he's really a young Magus? No, it's never really directly stated word for word in CT (no "I am Janus"), but it's implied and sort of indirectly stated, so it appears pretty much obvious.
Translator Ted Woolsey was the one who made things more complicated than they were by creating a specific name, "Entity" (with a capital E), even though the Japanese version only spoke about dareka (someone, something, etc.) and the planet.
Some people out of Japan find it curious that CC never tells us much more about the Entity. But in fact, CC had a better translation than CT as Richard Honeywood was directly assisted by Masato Kato. So, that's why it never uses the name "Entity" (although it does use the generic terms "entity" and "entities", presumably as simple vocabulary tributes); it just speaks about the planet, and people sometimes don't realize that it's the very same thing as the CT "Entity".
