The safeguard is "you go bankrupt if you fuck up"

Imagine there was some way for a trading company to execute billions of dollars of trades and they say "ooops, sorry, that was all a mistake" can you not see how that would be abused?

Now, the story also says that within a minute of the market opening, the experienced traders knew something was wrong. Do they bear any culpability for jumping on those trades, making their money off of something they knew couldn't be intentional?