I am not a conspiracy theorist, but what happened in this event bears watching, and could be a game "inflection point". Here's why:
1) The impressions of the beta community (both in guild topic discussions and here in the beta forum) about this event being "short" the horsepower to complete it are fairly homogenized. Many people were short in the absence of spending. This breaks (at least in beta) a fairly firm long standing (and recently stated) game position that you can get all the upgrades without spending.
People DID do that, but it seems very few. If 1 out of 10,000 can do it, that single person does permit the "you don't need to spend diamonds" story to be the "truth" but... hmmm.
2) We called out the shortcomings, now we wait to see how it's addressed in the live game.
3) If live users get the same "roll of the dice" we got, then it's clear it's not a math error and it's 2 data points - ad maybe a new design for games.
4) Our next event game for beta will also teach us quite a bit about a possible shift in event strategy. If our next game is going to keep people short of the prize completion goal without spending diamonds in a similar way this one did, then 1 data point becomes 2, or even 3... and that's more than an error in design math, probability or missing the event box - that's a trend.