What you should know is that Argentina had nothing at stake going into this game as they have already qualified so they only played this game for formality sake because whether they win or lose will not change the standing on the table as Argentina is sitting top of the table.
Anyone that bet on Argentina to win was really taking a big risk because it was crystal clear that they will not this this game seriously so there is nothing special about Argentina lose to Ecuador.
For Argentina, it was just a game of rules and a chance for new players. Since they have already qualified and are at the top of the points table, why should they take this game seriously and work hard?
Gamblers should have kept these things in mind when gambling and should have ignored such matches for betting. Because after scoring the goal, Scaloni will definitely try to keep his key players safe and avoid risks, no matter what the outcome.