I would send a formal letter to the costomers explaining the situation and you position. It sounds like the HO's are getting dooped by the GC. The HO's need to lean in the GC in one form or another. You may have a ligitmate gripe too. If the GC is blaming you for the charge and you are not making the charges AND if you contract with the GC does not state anything for such charges, I would start pushing right back too. That can ruin your reputation. That is an negitive impact on your company business and someone can be liable for that. I am not saying suing there are other options like you local business beareau or talking with the GC directly.
