hidden key switches in piano roll

After importing (xml) a chamber music score to Dorico 3 from Sibelius, there are key switches in some of the midi (C0 and such)-- but they aren’t visible in Dorico.
I can hear them in Dorico, but I only confirmed their existence by exporting the score in midi and viewing it in a different application.
I’ve tried “selecting” the invisible C0 commands but no luck.
So Dorico knows they’re there, because it’s playing them, but won’t show them to me in any way I can select/delete them.
Does that all make sense? Any help would be appreciated. I’ve done enough revision already that I’m really hoping to not have to go back to Sibelius, troubleshot there, and re-export.

If you are talking about KeySwitches that are playing back, you will likely need to handle those through Expression Map changes.

Can you perhaps see the notes in the Play mode piano roll?

Thank you for the response, v helpful.
I figured out that the “hidden” C0 are appearing, in Dorico, in the “playing techniques” lane.
There doesn’t seem to be a way to erase them (they can’t be selected (?) and the eraser doesn’t work on them.
However, as you suggested, I was able to set the expression map to ignore them.