It naively stops at the first column of the first line whose value is a plausible m/z value - and the mass is plausible for z=1. We should keep looking for others that may yield a higher charge state.
Also note that even if we do this, if the first line happens to describe an actual z=1, we'll get the rest wrong. We should examine all lines.

We should just work around this by enabling the column picker capability found on the small molecule version of this dialog (see issue 429). We can just skip the attempt at figuring out column order when the user has gone to the trouble to lay it out for us.

With the new proteomic column picker UI this is no longer an issue