As far as I can tell, apps installed to Private Space aren't able to have shortcuts on the Home Screen.
Might there be an implement to allow apps installed in Private Space to be added to the Home Screen and appear/disappear as the Private Space is unlocked/locked? Basically a Home Screen overlay that is visible only when the Private Space is unlocked and allows Private Space apps to be pinned to Home. (Private Space app widgets could also integrated into this.)
A nice feature to accompany this would be the swapping of app icons with the unlock/lock, causing another app to take its place on the Home Screen when the Private Space is locked. I would do this with my browser, keeping my private browser that has all my open tabs, browsing history, and bookmarks hidden from view while Private Space is locked, replacing it with a different browser (the same one without the data) that doesn't have any sensitive data but still works to access the web.