I think there are a few things that could have happened here.
First the obvious ones:
Fraud that both knew was fraud occured. I don't think that's likely but people are people.
Something Apple calls "fraud" happened that may have been something more arguable, and a strong personality ran head first into a brick wall. This happens a lot in the iOS/Mac AppStore process, as anyone who's tried to moderate this situation on behalf of anyone else can attest.
The less obvious one:
3 Lots of high reviews were put on the account by very satisfied developers. These reviews are suspicious looking to a programatic or non-programmer human reviewer who's unfamiliar with the product because the reviews are:
a. Often from the same IP (satisfied companies using docsets, etc).
b. Done from bulk license purchases.
c. Done from accounts that may have otherwise been found to be or suspected to be fraudulent (because the users have sometimes been fraudulent or "fraudulent" developers themselves but were writing a legit review in this case).
d. Overwhelmingly, brain-tingily positive.
e. Done from wierd networking locations (devs do that stuff, also, Dash is very useful for offline downloading, so wierd network situations).
f. Done over VPNs (because devs are the audience).