If multiple people have access to a shared calendar, is there any way to
see who created a specific appointment? Also, is there a way to see
who has modified an appointment? I've tried looking at numerous
columns which sound appropriate like author, creator, etc, but none
contain the information I'm looking for.

Along those same lines, I see that there is a 'created' field which
contains the creation timestamp, and a 'modified' field which also
contains the creation timestamp and doesn't change even if the
appointment has been modified. Is there a column that I can view that
shows the timestamp of when the last time the appointment was modified?

I am needing this information for a legal request. Even if the
Groupwise client cannot provide this information, is it possible that
it's stored in the database and could be queried in some other way, like
soap for example?