The tap also sends the values below, exactly as listed. The server keeps a salted hash of each marked reading, not the value itself, and compares the set with the other members' sets: the more readings two accounts share and the rarer that combination is here, the likelier they come from the same device. It also keeps a random storage id this app leaves in your Discord client (in its localStorage and its IndexedDB). That is how the moderators notice when one device verifies several accounts. A match never stops you from verifying.