I just wonder what the rationale of leaving his comment there was. Perhaps there's a sound rationalization of which I am unaware, and knowledge of such would help me be a more effective reporter in the future.
The only logical explanation that comes to mind is that this reported post in not handled by the same moderator which deleted previous posts. Although there are rules, their interpretation is not always identical by all moderators - and I have read such an interpretation more than once by the moderators themselves.