Hmm, everybody is running to your defense, but you are feeling guilty for a reason.
I've offered bad trades to people, but it's been a really long time since I've offered one that bad (particularly considering Gomes's injury).
True story- I offered a newbie owner in a league I commish this year Jim Thome, Jeff Francouer, and Javier Vazquez for Alfonso Soriano and Prince Fielder.
HE countered with Soriano and Fielder for Francouer and Saito. (Note, this was when Soriano had just taken the #1 spot and Gagne had only just discovered that he MIGHT be going back to the DL)
I never even CONSIDERED accepting the trade. I felt it would be unfair for me to take advantage of my leaguemates in such a way, especially considering the fact that I was commish.
Gomes and Escobar for Beltran is a horrible deal. If your trades were reviewed by league votes, I believe the overwhelming majority of leagues would vote it down immediately. The commish decided to let it ride, most likely because he didn't want to feel as though he was too active in league transactions.
In this case, I think (scratch that, I know) his better judgment would have been to veto.
If you can build a team of superstars through bad deals like that, then by all means, go ahead and do it, but that doesn't sound like a fun league to play in even for you, much less all of the other now-disgruntled owners you've probably created.
Deals like this are BAD for fantasy leagues. I personally never want to be a part of one of them.
I want both owners to be making an honest and informed attempt to improve their own teams. Deals made out of apathy or ignorance are never acceptable. That's my philosophy. I think you'll find the more knowledgeable and experienced (perhaps adult even would be a good adjective) fantasy players will tend to share this sentiment.
Like others have said though, you only accepted a bad trade, you didn't propose it. You aren't "guilty," but you aren't smelling like a rose either.