Sounds to me like the Reds are trying to make sure they don't have to pay anybody to play in 2004. When Larson did so poorly they had a problem: how to cover third base next year without shelling out any money. Probably Zeile wanted to be paid, so he was not an option.
So the Reds divert from the "pitching, pitching, pitching" plan to take somebody who may be able to play third and won't require much money.
On a positive note, at least in the minors, Hummel seems like a hitter who doesn't strike out too much. The Reds could use a few of those. Even if he is not a dynamic power guy.