You made a good choice.
I would let them deal with the contractor that made the mess, you never know what they used up there and without that knowledge and a msds, you could cause a bad reaction that could be harmful/deadly and probably cause damage to the shingles, you just never know.
It is better to be safe than sorry and keep yourself healthy.
John has some good points about being used, you just never know what the real situation is, there is a good chance that you were being setup to take a huge fall.