Can you clarify what you mean by a Prosit "score"? If you use Prosit to build a spectral library, then you can get all of the normal spectral library attributes like "Library Dot Product" in the Document Grid. But, we don't calculate anything on-demand for Prosit in the Document Grid. You would need to build a spectral library using Prosit in Skyline. The only thing we do on-demand with Prosit is populating the Spectrum Match graph with Prosit predicted spectra.
If you can give us more detail on what you are trying to achieve, we may be able to provide more help.
Thanks for posting to the Skyline support board.