He made the offer right after the Teixeira signing, which was about a week before the report. He kept it secret when it was a possibility, but now that's it dead it doesn't matter.
http://blogs.denverpost.com/rockies/2008/12/30/rox-agree-to-ship-vizcaino-to-cubs-for-marquis/
Luis Vizcaino to the Cubs, Jason Marquis to the Rockies.
I don't think it's fair to put him in the same sentence as Tex, a guy who was priority #1 for the FO and they failed to get him. They may have talked about Dunn but as far as we know, there has been no interest.
Just remember guys, this isn't like the Santana thing where the Twins were intent on trading him and ended up getting lesser value. The Marlins are in no rush to deal Hanley and would probably have to be blown away to agree.