I’d misunderstood the divisi concept when I originally input this:
What I really meant was two solo players playing, with the rest of the players silent, but the labelling doesn’t reflect that (because of my misconstruing the routine). I suppose I must have expected my Ctrl+X ‘solo’ instruction to show above both solo staves, but of course it doesn’t.
So - I tried editing the divisi dialog. I tried adding and subtracting staves from within it, and nothing worked. At one point I thought I’d got it right when the dialog (and the score) correctly showed Solo 1, Solo 2 and gli altri. However, this led to everything in the standard (tutti) 1st violin staff being removed completely in every bar following the divisi section (indeed, in one attempt the actual staff disappeared). How do I salvage this?