Work-around solution I came up with:

If you have about double the pre-printed forms you need, you can try this.

Align so that the top forms are good.
 
Print all the W-2s that you need. The top ones you will keep, the bottom forms you will discard.

Deselect the first employee and reprint.

The employee forms that printed incorrectly on the first batch due to being on the bottom, will now be on top.

Discard the misprinted bottoms. Keep the tops.  Repeat for each set of forms.

Aggravating problem, but I hope this helps.