I kind of doubt this is true.
The Brewers GM said they made Cordero an offer. Cordero came back saying he got a little bit more from the Reds and wanted the Brewers to up their offer. The Brewers GM said that he wasn't getting into a bidding war and made their best offer.
Cordero was out to maximize his paycheck.Nothing wrong with that.
It's not believable that one morning the Brewers GM was stunned and surprised that Cincy came out of nowhere and scooped up Cordero