[FlaminSarge]

"Votes"
{
    "tf2items_randomizer"
    {
        "title"        "Turn TF2Items Randomizer {!tf2items_rnd_enabled|onoff}?"
        "type"        "confirm"
        "command"    "tf2items_rnd_enabled {!tf2items_rnd_enabled}"
        "admin"        "sm_vote"
    }
}

Try that.

Also in reply to failhorse's PM, putting the cvars in the server cfg works.