Quote from fhl:
He simply said that he didn't remember, he didn't say that it was not red and he didn't respond accordingly/promptly. It is to early to tell if he screwed up.
Here is how I think he screwed up. First, he had a responsibility to make sure he was confirmed out immediately, on every single order cancellation request, but he didn't know how to do so (how to look for the red order status code). Second, from the time he issued the cancellation request, until almost 40 minutes later, he did nothing to alert IB to the problem, or to ask IB to determine whether or not his order had been executed and resulted in a position requiring further management on his part. He lost 43 pips because of his 40 minute delay. He delayed until he noticed that his new position had unexpectedly showed up on the TWS. He should have been all over this problem 40 minutes before that time, so that any loss would have been far smaller, and so that he would have been at least able to make a case that the inevitable small loss should be eaten by IB and/or by the counterparty.
I'm willing to consider placing some blame on IB for possibly bad documentation which might have led to this guy's uninformed use of TWS and his resulting mistake.