I refuse to wire any kitchen with out the final cabinet plans and appliance list. Too many times I have had happen exactly the type of thing that happened to you. Not matter what I think they should pay for the additional circuit if it was not in your bid. The sheetrock work and other repairs is what usually gets sticky but since the GC is offering to take care of that you should be ok. I'm not sure what I would do if they were refusing to pay for the additional circuit though. I guess if it was an easy of enough run I would probably just do it and move on to the next job. I hope things work out!
Curt
