Matching Participants to Contacts
A meeting gives you a display name, not an email address.
The console tells you who is in the room, and tries to connect each participant to one of your registered attendees. Sometimes it cannot, and the reason is worth understanding: Google Meet only provides display names, not email addresses.
So "Sam" in the participant list is not automatically the Sam who registered.
Steps
Let the automatic matching run first
Participants are matched by name, and by the way they joined — someone who came through their own registration link is identified on the way in. Most people match without help.
Look at who is left
Unmatched participants are usually one of three things: a nickname that does not match the name they registered with, someone on a shared or family account, or someone who never registered and was given the meeting link directly.
Match them by hand
Pick the registered attendee each unmatched participant corresponds to. This is what gives them a real attendance record and a watch time.
Do it before you finalise
Matching first means the watch times land on the right people. It is much easier during or just after the session, while you still remember who was who.
Result
Everyone who was in the room is connected to a contact, so the attendance reflects reality. Anyone left unmatched counts as a participant who was there but is attributed to nobody.
Warning: This is the strongest reason to share the registration link rather than the meeting link. A registered attendee is identified on the way in; someone handed the raw meeting link arrives as a display name you have to place by hand, assuming you recognise it at all.
