They definitely deserve answers, you are right. But jumping to "This was an op and the DC police as a unit were in on it" is approaching wheelhouse of the crazies who instigated this whole debacle. That runaway cascade of believing lots of little things that could be possible is what led to millions believing in dumb stuff like Mole Children being kept as slaves by Hillary Clinton and friends.

Unless something more sinister emerges the simplest explanation is probably the best - there some cops who are far-right sympathisers and there are incompetently managed and organized Police forces. Both of those things are already demonstrably true and explain how the response quite well without introducing a grand conspiracy.