This is my last hope of somehow getting this straightened out. The game developers that allowed A Gb to be deleted with Fps on them allowed this to happen, I find this to be unfair to any players that have been investing in GBs to let this happen. It simply should not be allowed to happen in the first place. Just like you can not delete a residential building because you have to few residing in the city. I would like to see this change made it would hurt no one and keep this from happening again.
You have to consider your contribution of FP's as a gift. Just as is the case with any other gift, the receiver can do what ever they want with that gift. The gift is not yours to control. Most of the time, that gift will bring you rewards, but sometimes, it brings you nothing.
In the situation you mention, I would have to ask if this were a friend or guild-mate who solicited your contribution or was it solely of your doing. If it were a friend or guild-mate who solicited it, you may want to work with them to be made whole, especially if they did it on accident. However, there is no guarantee. We call it a contribution for a reason. Once you contribute FP's they are no longer yours. I have an entire page of GB's that I have contributed to, that are well over 6 months old. 1 of them well over a year and a half from an ex guild-mate. Most are skillful contributions (some call that sniping, but sniping is so broad a term) to neighbors. Regardless, I realize the "risk" when I contribute. Once they are out of my bank or bar, they are no longer in my control.
It bites what happened to you, but it is part of the game. I had a guy delete an Arc (on purpose) in the 30's just to spite me for locking in P1 at lower than he wanted. It sukked, but I got over it and can now laugh at it and have a great story to share with others. This will pass and you will have greater challenges than this, trust me.
Hope it works out for you.