The Fed's decision was a very big surprise to most, from what I've read. Just google "taper surprise" to see for yourself. Also, this was a massive move upwards, so the argument is that over a billion dollars of bullish bets made at the exact same milliseconds is hard to explain away as another contrarian play that payed off well.
Still, skepticism is healthy, and it's possible that no scandal is involved.
The mainstream financial headlines generally regurgitate what the Fed wants to message. While certainly 'most' were surprised, many weren't.
Tapering was dependent on econ data, which simply hasn't been there to support it. I know plenty of people who were betting that it wouldn't happen, myself included. Good overview of why from before the announcement here:
Yes - most journalists/analysts prefer to be wrong together than wrong alone, so there is usually a lot of groupthink. The previous fed minutes suggested that most members wanted to wait to taper, unless data improved, and data didn't improve. It seemed obvious to me that the taper was nowhere near a done deal.
Still, skepticism is healthy, and it's possible that no scandal is involved.