they typically drop the hammer pretty hard for xtrading in idlescape, I'm not too sure about their detection methods but they take a very hard stance against xtrading. I recommend against it if you value your account.
this is coming from someone who xtraded and had the hammer dropped on me. I had no discussion of trades in-game or any similar suspicious activity on my account. mods spend a decent chunk of time reviewing unusual market trades specifically to catch xtraders.
I will also say that 10fg/mil is an absurd ratio. more realistic is 2-3fg/mil, tops. I have cycled roughly 5b on my own account and sitting on almost 2b at this moment. not worth 10k fg for 1b.