Unfortunately none of the answers provided are all that thorough:
Fg is not refunded. This and many other common questions are answered here:
https://forums.d2jsp.org/info.php?p=14D2jsp offers mediators free of charge to ensure trades go smoothly without a scam. There is no reason not to use this free service, especially for larger trades.
Repays happen often, you can see an example of how many people are interested and go through the repay process here:
https://forums.d2jsp.org/forum.php?f=293If you have further questions, feel free to pm me. I'm one of the moderators who handles investigations in the Scammer Accusations (along with eerock, currently)