I'm not sure how that would help. They would have to generate a matching hash on their end, giving them a lookup table to work backwards from hash to email address.
Now if they wanted to supply a list of hashes to the public, then you could check your own without knowing any of the other addresses used to generate the remaining hashes.
Now if they wanted to supply a list of hashes to the public, then you could check your own without knowing any of the other addresses used to generate the remaining hashes.