DC camera speeding tickets are issued to the registered owner of the vehicle and are the registered owner's responsibility unless the RO provides an affidavit with the name and contact information of the individual authorized to operate the vehicle or an affidavit that the vehicle had been stolen, along with a police report #.
For Hertz, nothing is going to matter because it has paid the violation as the registered owner and charged you for the ticket and an administrative fee.
Although the amount may seem high to you, it's not by DC standards and is likely $150 + admin. fee.