The pivotal integration only allows for 2-way integration only if originally pushed from aha initially. Even then it's pretty limited to status and description.
If I create an 'feature' in aha which maps to an 'epic' in pivotal, and someone adds a story for that epic in pivotal, then that story should be auto imported as a new requirement for the feature in aha. This is a very common use case since our dev teams will add technical stories for certain epics (features) and these will not be reflected in Aha.
Imported stories that we're previously in Pivotal, do not update in Aha when updated in pivotal
Comments do not link with stories or epics in any direction. Comments should sync 2-way for all epics and stories.