OK. The way it's supposed to work is that the "Reset Metadata" only zaps the data from the *1 file. You then have to hit sync to save the (empty) fields. In the second stage of the sync, it notices the missing data and gives you that message. If you hit "Yes", it'll fix up the data as best as it can. Then you need to sync again.

If it's not working, you probably have some bogus files.