Sorry to know about the trackpad crack issue bro. so far havent seen such automatically getting cracked issue reported by any of our audience or in general. and yes any damage is covered under applecare+ claim. we have to pay the claim fee though. so before warranty ends you may get it checked at apple service center if its manageable and you can continue using it.
applecare+ does come with unlimited claims. so during the care period you can claim anytime.