I would Retranscribe the notation (MIDI Menu). Be aware, though, that doing so will strip out any expressions, slurs, articulations, etc. that appear in the file. If there aren't any of these, Retranscribe should get the job done.

However, take a look at the Quantization Settings, and the More Quantization Settings.

In the pane for Rests there are two options about dotted rests.

That does work, thank you! But unfortunately that's changing my B naturals to C flats (in a key signature of 3 flats)

In a key signature of 3 flats you can have C flats as well as B naturals.

It depends on the tonal context.

If the chord is Ab minor, then the third is C flat.

If the chord is G major, then the third is B natural.

Unfortunately Finale does not understand tonal context.

You will have to correct the spelling yourself.

As Peter says, set your key sig for C minor to get three flats with B-natural instead of C-flat....

Good to know! Thanks very much!