I am afraid that there is no easy solution to this as the activity entity that is the smallest common denominator of email and phonecall does not have these fields.
This is also why you will not find it in the regular views in CRM.
The only workaround I can Think of if making a retrievemultiple plugin that adds this information to the response which switches based on what the type is. This will require a developer and is not that straight forward and will also create some inconsistencies in the system (like with exporting to excel).