02-06-2020 12:35 PM
Fortunately you correctly listed it is for parts or not working, and didn't undermine this by making any claims about it.
This should mean that eBay would find in your favour if the buyer opened a money back guarantee case because it didn't have a passcode. None was offered or mentioned in the listing. They don't have any cause to complain - eBay's definition of "for parts or not working" reminds buyers that this can mean they're missing essential components.
In any case, it's a bit late now to worry what they might find on your phone if they can get into it! If this is a real concern it might be worth offering them a refund on return.