Can't show rests in 2nd voice

I’m trying to show rests in a 2nd voice, but I can’t get them to show. I have “starts voice” selected
Annotation 2019-03-13 141311.jpg
, but no rests show when I move to the next bar (but if I put in an explicit rest, I get two rests in the voice!) How do I show the rests in the 2nd voice?

Try Can't add bar rest - Dorico - Steinberg Forums

That only solves the problem sometimes. For example, in this case I want to show a rest in the second voice from bar 77:
Annotation 2019-03-20 103219.jpg
I can’t see anywhere to set starts voice, and as I say, if I manually insert a rest, Dorico inserts two rests:
Annotation 2019-03-20 104108.jpg
(surely a bug?)

I’m still stumped.

What do you want? A whole/semibreve rest? If so, set the caret at the start of the bar, use V to get it to the correct voice, type Shift+B then type rest into the popover and hit Enter.