I understand that you would like to receive the challenges, so that the quality of the problem is much better. You should provide prizes for the authors of such challenges and definitely add these challenges to the test cases in the practice.
But how on earth could you modify the status of already accepted problem in the official contest? You should not provide a misleading information that the problem is accepted. In the first problem the status was clear - there are no results until the end of the contest. But once the results appeared, they should not be changed.
You could have made the whole formula harder and not provide any information about the results until the challenge phase is done, that would be fair. But failing accepted submissions is not ok.
Could you please revert the ranking to the version from the end of the contest?