I do not know enough Japanese to say for sure, but it looks like the primary (and only) definition for 密告 is not right. The definition is “secret information.” However, this neither fits the provided example sentence, not does match the primary definition in other dictionaries.
Based on other dictionaries [1, 2], the primary definition seems to be “anonymous report” or “tip-off.” JMdict [2] does list “(secret) information” as a secondary meaning. I believe it is referring to the leaked information in the anonymous report itself. However, the term “secret information” is incredibly misleading in English as it carries no nuances of a tip-off.
I believe the primary definition should either be “anonymous report” or “tip-off.” Can someone more familiar confirm or correct me please?
I was very confused just now by this because I had added the user synonym “secret info” when I first got it as a lesson because some of the earlier words including “information” have built-in hidden alternatives with “info” and this one didn’t.
But before I allow an item to Burn (I use Double-Check but have it set up to only allow marking things wrong and retrying different answers, I don’t use it to mark things right), I always type the additional definitions I know and check them so that if I don’t, I mark it wrong and let it demote.
So this came up now for a Burn review — meaning, the last time I saw it was in September, before this was reported — and I gave “secret info”, it was marked right, I opened the full listing to see if I missed alternate definitions, and was totally confused!
In the future I need to remember to check the dictionary before adding synonyms, I guess!