Tom, not taking sides here, but Turtle is right, you asked! He and several of us answered, going off original info. If the trailer owner was on scene, was the actual spotter, thinking clearance was good, you needed to disclose this info in OP. IMO, a spotter, especially trailer owner, that you are helping is now responsible, so yes this added info makes a big difference. Her insurance should pay and possible raise in insurance to her.
If you choose to help with the deductible, good for you.
Jerry