I don't know but I really doubt that.

When you search for a service you get the current status and you get the option to report a problem.

The minimal you expect from such a service is to keep track of how many % of users are searching also reports an error. There might of course still be errors but that alone surely can't be it. But please correct me if I'm wrong.

edit: and their own description only mentions actual reports https://downdetector.com/methodology/