I ran across a similar situation myself in the past 24 hours.
What ended up working for me was:
Scenario: I had a stave with arco material in the Stem Up Voice, and pizzicato in the Stem Down Voice. Both voices were on the same stave. This can present a problem because our connected VSTi plugin uses a key-switch to get the pizzicato sound. The plugin isn’t really meant to play pizzicato and arco sounds at the same time. So, the pizzicato voice needs his own unique instrument/channel to avoid conflicts here.
To get this to play back correctly I did the following:
Created an entirely new section/player in ‘setup’ mode, and set the proper Tutti Violins Combi instrument. I made sure this new stave was directly below my problem stave. Since I entered a new ‘section’, by default, Dorico gives me tutti Violins from HALion Symphonic Orchestra for the stave. If I want a different plugin or sound to be used at this point, I could then do so from the play tab.
I used selection filters from the Edit menu (in write mode, galley view) to select only my stem-down voice (the pizzicato stuff).
After insuring all my pizzicato stuff was selected, and nothing else, I used over-ride controls in the bottom panel to ‘mute’ all of the selected pizzicato notes. This allows me to keep a stave as desired for visual/printing purposes, but the pizz notes on this stave won’t make a sound.
I used “Paste Special” to put a copy of everything selected (my pizz notes) into the empty staff below.
I made sure everything on my new stave, and only these notes were selected and ‘un-muted’ it all.
Now I have a stave that plays back properly, as well as one that offers the visual effect of having multiple voices/parts on the same stave.
In engrave mode, I can adjust the Master Page to filter/hide the pizzicato stave from view in write and engrave modes. At this point, all staves are visible and I can work with them from Galley View, but filtered staves will not show up in write or engrave view.
Now I figure that in the future it’ll be best to keep some hidden staves handy if I need to work with multiple articulations or bowing styles on a single divisi stave. If there is a way to assign stave voices to independent instrument plugins/channels, I haven’t found it yet.