Fantasy Football Ruling Issue

[Mark L]

Ok here's the jist of it, I'm sure someone else will step in with more detail.

In our 2+2 dynasty (deep keeper) league two teams agreed to a trade. I forget the exact details but the two key players were Frank Gore and Deangelo Williams. For whatever technical reason in the league the trade did not go through when it was expected to. (I believe this had something to do with a game on a thursday and yahoo messing up.)

The player trading for Gore wanted him because he has a shot at making the playoffs. He ended up losing and was thus eliminated from the playoffs. (I believe he would have lost even had the trade gone through.)

Now he no longer wants to do the trade, stating that the value of the trade has changed. The guy on the other end of the deal is a little pissed, and says that the first guy wouldn't be backing out if williams didn't have a big game.

The league is kinda divided on what to do here. Thoughts?