Freezing fog pops up from time to time, but not when it's this warm. That's just FZFG. I think as steex said, it has to be a "typo", as I can't find any indication of FRG
actually meaning anything anywhere.
The current TAF makes it look like conditions should clear up relatively soon visibility-wise. For instrument approaches, visibility is the more important minimum (rather than ceiling) in determining whether an approach can be made, and nothing here looks like it would be restrictive in that sense. Also, winds don't look too bad, so I'm thinking there's no need to divert.