migu and gilgul shevu'ah

My son asked me if someone who is exempted from a shevu'ah because he has a migu can be forced to take that same shevu'ah through gilgul. What he seemed to be driving at is whether migu removes the chiyuv shevu'ah or whether it just prevents Beis Din from administering the shevu'ah, but the chiyuv remains. (I assume someone might also flip the chakira into a question about the geder of gilgul shevu'ah, but that approach is not so clear to me and was not the direction my son was headed anyway). I could not think of a case offhand that would provide an answer. Since my brainpower is fading, I figured I would throw it out here…