Courtesy Accidental plug-in Add fails to add all the courtesy accidentals

I have an arrangement of Giant Steps. Since it changes keys frequently mid-measure, I wanted to mark ALL the accidentals, with sharps and flats symbols appropriate to the current key center.

I enabled the courtesy accidental plug in, and ran it to add. It added some courtesy accidentals, but was hit and miss, meaning I still have to scour through with my own eyeballs to add them.

In attached file, notice the base line, 6th measure of second staff where the Eb key center is marked in green.
See screenshot of this measure.

Loading the file into MuseScore 4.4.2 on Windows 11
Plugins menu, Composing/arranging tools, Courtesy Accidentals/Add

The plug in does not add all the courtesy accidentals applicable for the song.
For example, it misses this measure in the bass line, failing to add a flat mark on the second a note.

--Am I doing this wrong, or misunderstanding the feature?
-- Is there just a bug, where the plug-in incompletely navigates through the music?