Okay, I figured it out. After some experimenting, I found that I could fix it in Tag&Rename. The v2 tags looked fine in T&R, and in other programs like Winamp, but they weren't being read by Emplode. After playing around with the T&R settings, I found that if I unchecked the option to "Write Unicode data into ID3v2 tags" then the v2 tags were fine in Emplode as well.

I don't know what Unicode data is, but Emplode doesn't like it.