Contractor Illegally Dump Waste In Public But I Am In Trouble With The Court.

Hi Reddit,, this is my first time posting on here. I am not sure if this was the correct sub reddit for this issue. The issue is my dad was fine $5000 because contractors illegally dump waste in the middle of an alleyway and it was caught on camera by one of the neighbors. At the time of incident, no one was home and the contractors used my dad's driveway to move their truck and dump waste. We got fine by OAH and decided to deny the violation as we do not know these people. We are going to court soon about this and am seeking advice on what to do next?

Also want to note we live in Washington DC and aren't financially well-off so hiring an attorney is out of the question.