This topic needs an update since the tourney rules have been updated with the following:
"If, through a card effect, a player “cannot win the
game,” he cannot be awarded a win or a modified win
for that match. (His best possible result is a draw.)"
Also we know that:
"If the time limit has been reached, the player closest to
his victory total (in power) earns a modified match
win and his opponent receives a match loss."
So what happens if the player running The Maester's Path is the closest to his victory total (in power) but did not place all his Chains?
He should earn a modified win and his opponent gets a match loss. He cannot receive a modified win so he gets a draw if both players have the same power total. Otherwise, both players receives a match loss.
What happens in a Melee game? The rule above is only in the Joust section of the Tourney rules.