Sorry to say but you are not trying to analyze the scenario and simply generalising the fact that in both cases the last passenger has cancelled his/her ticket.
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In this entry, prediction takes for all the 3 people, first two people gets confirmed against the very same quota they had booked for and the last pax cancels his ticket. We follow the least status and mark the entry confirmed since:
1)...
more... Prediction has taken place for 3rd passenger after which he had cancelled his ticket.
2) Even though the last pax has cancelled his ticket, the first two passengers has been confirmed against the same quota as to their booking quota.
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In the second entry, first two passengers are already confirmed at the time of posting the PNR at entry. Prediction there takes place for last two pax (Only). At time of chart preparation, last two pax cancels their ticket. Hence the PNR is marked Void (Since all the passengers for who prediction was taking place has cancelled their ticket)