Welcome to the world where of you want to send non-blank requests to more than a few people per month, you have to pay LI through the nose. Nope, sorry. If we both already know who each another are, blank it is!
Regarding the second last, there’s a chance that only one person will remember who the other person is. If you have a super intense networking night, things might get a bit hazy.
But these are fair thoughts, so cheers for the feedback!