Baseline Start and Baseline Finish attributes are missing and cannot be added as columns in the Roadmaps Grid view. However, these attributes are available and can be utilized within the item events in Timeline view.
All supported versions
Events are only applicable to the timeline layout. The configuration for adding an event, may show more fields than what is available on the 'Roadmap Items' grid column listing.
Grid only has fields from the 'Roadmap Items' object, not from the investment objects.