I run a league and I would not have vetoed it because if I don't think it's collusion, let people do what they want with trades. I don't think it's a fair trade, Megatron is much better since Dwyer may be the 3rd string back in a couple of weeks, but I could see why you would make that trade.
But, my league has a rule that if 6 managers vote against a trade, the trade gets vetoed, and won't go through. So people have to live with it. It's the only way to fairly police trades.
Please help: viewtopic.php?f=18&t=528355
12 Team league
QB Matt Ryan RB1 Arian Foster RB2 Fred Jackson WR1 Welker WR2 Cobb Flex Ridley TE Gonzalez K Hartley DEF HOU
Bench - Bolden, Vereen, Tate, CJ Spiller, DHB, Ryan Broyles, GB DEF