Something real subtle probably, like enough of the redacted areas accidentally containing something like looks like SQL. Like WALTER contains ALTER, CASEY contains CASE, etc...enough to add up the score to fail.

Hopefully more convoluted than simple substring matches like that, but I've seen WAFS do that. If it is adding up substring matches, there is stuff like "subscription_update", "null", "created", "discountable", "total_count", etc, that would set a high floor.