I have yet to hear why the charges were dropped, but...
Actually, I don’t see how they could force him to reimburse the city for the cost of the investigation unless he is prosecuted and convicted of a crime.
Imagine how bad this could be if every big city decided to make conservatives pay for every “investigation” into hate crimes, like displaying the American flag or something.
Look for his next court appearance to be when he sues the city for millions and a black jury awards it to him
There doesn't need to be a criminal conviction. The government will make their case in civil court that he did it.