Let me take a guess..... you spend more than $2000 of your own money to wager that $332k.. right? How is a reward of $100 worth it, if you lost so much money trying to achieve it? Even if you multiplied it four times as you said..... then you still made a huge loss on it.

I do not chase these challenges, because it is basically designed to reward a few whales..... the rest of the people get a fraction of a percentage of the big amount. Yes, it is a little bonus... for the money you spend on the site.... but it is so small... that it makes no impact on your losses.

Reaching $332k with only $2000 of net loss is very difficult IMO. It's less than 1%, 2000 / 332 000 = 0.6% On which games do you have a such small house edge? AFAIK only blackjack is offering such a small one. But you need to be a very strong black jack player, who never makes mistakes. So I don't know if he is one of them but only few people are able to achieve that IMO.
Guys, losing 1%, or whatever the house edge for the game you are playing is, is never guaranteed. Some times I wish I'd lost only the house edge and other times I'm in big profit after making just a few rolls.
So, reaching $332k with only $2k of net loss is not "very difficult", neither it is "easy", it just depends on luck. You can be in profit of $1 million after wagering $300k. I'm pretty sure there are such cases.
As you say you have been in big profit after making just a few rolls, but what about after thousands ones? I doubt anyone sane will gamble more than 10% of his bank roll at each bet if he's trying to reach such wager amount. It means 1660 bets have been made at least with an average of stake $200. On 1660 bets you are more likely to lose the house edge than to make winnings because it's not a small number.