I completely agree with you. That's a good report.
My point was that it's not that the report is marked as good automatically if the topic move to another board. As the moderator must select the status manually, it's possible that the report is marked as bad.

As far as I know, when a post is reported and the post is deleted, the report is automatically marked as good even if you have reported the post for something else.
It's not the same when a post is moved. The decision should be made by the moderator and I agree that the moderator should mark the report as good.