I need help getting the catacombs

So I've had 6-8 (I've been adding more) graveyards for like 12 days non stop, and the wiki says there's a 12% chance to get the catacombs

However. I'm on peaceful mode because it's my first playthrough, but if I need to do a more difficult mode then I don't mind whatsoever, I just want to get to the first (or second, I suppose) island and i want to throw this game away because i can't get the stupid catacombs! I've even gotten magic dust by accident! I feel like I shouldn't have that yet! I don't even know where I got that or some old tomes! It'll give me everything but the catacombs