If it's BEFORE the pending order is about to be executed, you don't need a trade event, it doesn't exist yet.
Pending orders are manageable with OrdersTotal(), OrderGetInteger(), OrderGetDouble() functions.
Thanks for your answer.
I guess I really need a pre-trade event, which will alert my EA that a pending order is about to be executed so that it can check the price and indicators and delete the order if it is obsolete or execute it if all is well.
I can write code to do this, but I was hoping there might be an existing type of event I could use.