IIRC, Garner can select all bench positions and pitchers, with the approval of the NL office. One roster slot is reserved for the final vote in, remember last year?
Watching the Reds this weekend, I know who I wouldn't vote for, and that's Adam Dunn. He has to be the slowest player in the league, no range at all in left and a base clogger. I wasn't aware he was THAT slow. Dude can mash, but damn.