Alright here is how you could stop people from using "/itemtrade <account>" to scam people.
Make it so there is a 30 second timer that gets activated when "Cancel" is clicked.
Wait I have to wait 30 seconds for a trade to close!!! NEVER... Now here is part two of the trade update. In order for the trade to close before the timer goes out BOTH players in the trade must cancel or simply wait 30 seconds...
It would look something like this.
Questions, Comments, or Concerns.