They were specifically testing your assertion that a non-roll is treated as a pass, which disagreed with what they previously stated. Such a test can only be performed by letting the timer expire, which cant happen if the other people leave. So reading their chat log: Line 1, they loot a chest. Line 2, it asks them to roll. Line 3, the other player in the party helping with the test rolls(we know from context that they pass). Line 4(and 5), after 5 minutes have passed and the timer expires the loot is awarded to them.
So indeed, the system is treating it as a 4-tiered roll system. Need as tier 1(beats all but a better need roll), Greed as tier 2(youve indicated you want it, you beat anyone who passes or doesnt roll but still lose to any need or a better greed roll), blank as tier 3(you didnt say you want it, you didnt say you didnt want it - so you get it if no one else wants it - one would guess it randomly assigns if no one rolls anything but i havent tested this), and pass as tier 4(you didnt want it, you dont get it).
