...what the EXACT condition of that load was prior to towing, and that would have to be with timed and dated pictures that still might not stand up in court
The tow companies have their asses covered when it comes to issues like this, so you can know that THEY aren't towing for themselves, that a certain party called THEM to tow it, so you would have to find out who authorized the tow...and that's where things get even trickier
Basically, all responsibility of negligence will fall back on you just for having left the vehicle in a "no parking' zone.
Your companies insurance company will have to assume the claim.... if there were damage.. also, the cost of storage and the tow
A towing company will not put itself in jeopardy by towing something that might cost them. They know the laws of that particular State and County... you can be assured of that
I wouldn't try to go after it unless extensive damage was caused, and then you would be responsible for 'burden of proof' and it would basically be your word against theirs...
You were negligent. That is how a judge would see it. You parked illegally and you are responsible for the consequences