I could go either way. On one hand, Furcal and Abreu are both being sold low and Victorino and Weathers have value, but the addition of Dmitri Young is surprising and somewhat baffling. He just seems totally mediocre to me. Good BA, but otherwise not very valuable in 5x5
If the team giving Furcal and Abreu *needs* a first baseman, he could have saved himself the trouble of making this a 3 for 2 and simply added a comparable player off of the waiver wire than Young. Not a big deal, but if they're trying to sell the legitimacy of the trade on the guy needing a first baseman it could be a red flag.
It almost looks like it might be a collusive trade, framed as a 3 for 2 to look more legitimate.
I would ask for some reasoning. People who cheat are also stupid. Check the "last league activity" time on the managers tab (if it's a yahoo league) you may find that they have times within five minutes of each other every once in a while. Also ask them to explain themselves. They might misspell the same word with both yahoo ids if you get samples of writing from "both" of them.
There might not be any foul play, but I'd check it out. If there's no foul play and they make decent cases for why they believe they are helping their teams, I might not veto.