When creating a dynamic report, the report is automatically 'private'.
Your colleague can make this public by clicking on the lock icon. He/she will see a prompt appearing. After his or her confirmation, the report will be publicly accessible.
More information on public/private reports can be found here:
Can I change a report made by another iController user?
How do I create a private dynamic report?
Why can only I see my created report?
Why can't I remove a dynamic report?