Am I wrong in thinking this rest shouldn’t appear with my current notation options? For what it’s worth, I set the final hi-hat and kick in bar 8 and the first hi-hat and kick in bar 13 to ‘ends voice’ and ‘starts voice’ respectively, just in case that was required for the option to work.
Please ignore the incorrect count on the repeat bars 
Starts/Ends Voice Properties don’t work on percussion kits, so the circled rest isn’t at the start or end of a voice, meaning that the screenshotted option isn’t relevant.
This is expected behaviour.
It is within the percussion notation options though, and the kit is in a five-line staff presentation.
Regardless, the rest is really cramping my style and I can’t get rid of it… changing its colour does nothing and neither does Remove Rests.
It is not the start or end of a voice. The Notation Option is irrelevant. And Remove Rests doesn’t work on Percussion kits, because all it does is automate the Starts/Ends Voice properties, which (as I’ve already said) do not work on Percussion kits.
You could switch the bottom note into Upstem Voice 1, then F(lip) it, come to think of it.
Pianoleo coming in to save the day!
There’s still nothing in Dorico’s behaviour here that isn’t working as designed, though 
Yep, I agree with you on that now - that’s not to say that an option to suppress bar rests in other voices (like you can do with non-percussion instruments) wouldn’t be welcome
I have the same problem only with a slash. This workaround makes my slash into a regular note. Does anyone know something I can do to fix this?
Unfortunately I don’t think the same solution is possible for a slash, because when a note is put into an extra voice its notehead is always reset to the default.
You can change the notehead type, though, can’t you?
I don’t think that works for notes that you move into one of the extra voices, but I may be mistaken.