Inedible as in anything that isn’t food (ranging from something that would be dangerous, like glass, poisonous plants, or uranium, to something that is safe to eat but unpleasant with no nutritional value, like cardboard.) Eating the thing will be safe and painless.
Why that planet in particular?
if it can harbor life it can possibly sustain me. I’ll happily eat a spoonful of dirt a day just to get the fuck off this planet.
if it can’t sustain me, at least I’ll die in a cool way.