Becoming Independent? They already are independent. All MNT stations are, if you want to know the truth.
And why would this move happen? As much as MNT isn't a network, at the same time, it really would make no sense for WDAF to put MNT on a subchannel (A subchannel that would probably otherwise be broadcasting content from a diginet since most, if not, all of the syndicated product in KC is probably already claimed. They could do what Hearst did a couple years ago and start broadcasting second runs of talk/court/other shows on the subchannel but that would be an unlikely move. If for any reason, KSMO decided to jettison MNT to just put other shows on from 8-10, or whenever they broadcast the lineup and it were critical that MNT remain in the market (Any station could buy all the rights to every show on MNTV, since they also air in traditional syndication), It'd probably go over to KMCI first, or maybe on KCWE or WDAF late at night, but not a sub.