Isn't this criticism backwards? (Even if it were true, which if I have understood correctly it isn't.)
A high error rate in the diagnosis would lead to messy data which would weaken the patterns that the analysis uncovered.
But the analysis showed strong patterns.
If the data were messy but still showed strong patterns that would have meant that the patterns for a clean dataset would have been even stronger.
This criticism would have been relevant to make before the study, to warn the investigators about things they should improve to get a better result.