Do you want to track the interactions which were forwarded to callback? In the Interactions Details report, you can identify those interactions which were opted for callback and resulted in a callback. Interactions which were forwarded for callback may be cancelled after a time period set in the IVR script. You can track these interactions using the appropriate label.

Label - Forwarded to callback: Tracks interactions that resulted in agents calling back. Includes queued and non-queued interactions.
Type is callback: Lists all interactions marked for callback, as well as those that resulted in callback, and those that were cancelled from callback.
Label - Cancelled callback: Tracks callback interactions which expired - no agent was available in the expected validity based on the default time set in the IVR (currently max 6 hours).
Note:
Callbacks can be either outbound or inbound, depending on their type:
- Web callbacks of type “call me now” or “call me after a certain delay” are inbound
- Web callbacks of type “call me when agent is available” are outbound
- Callbacks created by the IVR script are always outbound
The web callbacks of type “call me now” or “call me after a certain delay” are considered inbound because these calls are made into an (inbound) channel and are otherwise treated the same way as ordinary inbound calls.