Hello Luke,
a Layout is the way of displaying the musical content. You can have as many layouts of one musical content as you like. If you change the musical content it will be displayed in all Layouts.
This basically leaves you with two options:
- create an extra player (as you suspected).
- let the player sort it out how to play the out of range note…
Note: if you create an extra player, copy the music over and do the corrections, you can then hide that extra player from the Full score layout again, so it won’t be visible there…