A session opens only if everyone on it held a passing check that was still current on the session's own date — not last month, not today. A check that lapsed on Tuesday does not cover Wednesday, and a guest who was never checked does not become checked by being in somebody else's room.
A check is good until the earlier of two dates: the re-verification interval that was in force on the day it was made, and the expiry of the document it examined. Neither is typed in here. Both are derived, so a date nobody remembered to update cannot quietly keep somebody on the air.
Every check anybody has recorded, newest first. Broadcaster records that a check happened — by which vendor, by what method, on what date, with what result and reference — and where the evidence is held. It never holds the evidence. There is no field here for a face, a document, a number or a frame of video, and no way to attach one.
The one thing in this program that is recorded rather than refused. Refusing to write down that an unchecked person was on camera would not take them off camera — it would only take them off the books, which is the one outcome this program exists to prevent. So it goes in, loudly, and it stays open until somebody with a name writes down what was done.