The GetStream entry concerns Activity Feeds, which should not be confused with Stream Chat.
Stream's migration guide describes changes between v2 and v3, including the activity model and identifiers. An older example using one set of fields is not automatically a valid request for the newer SDK.
Pin the product and version in the integration notes. Test creating, retrieving, and updating a disposable activity before migrating a feed, and verify that the application's identity mapping remains consistent.
Akousa