Plusnet screwed up installation and are now refusing to fix the problem.

[#1]

Last Monday (14/01/13)  an engineer came to install my broadband but the phone hadn't been switched on (he said there was no live). He moved the master socket to try and fix the problem but to no avail. He left to do his next job and I didn't have broadband or telephone.
I rang Plusnet and they said the engineer had come too early and that the phone wasn't due to be switched on until Monday afternoon. Sure enough, the broadband started working Monday night but my phone still didn't work.
Plusnet sent another engineer on Friday (18/01/13) and he said the first engineer had not done the original installation correctly. He managed to get the new master socket working but the original master socket is dead and so are all the lines that run from it.
I contacted Plusnet on Friday afternoon and again today (Monday) and they refused to fix my wiring to even though it was their first engineer that had caused the problem and the second engineer had only half fixed it. They said the only thing they can do is charge me £140 to send another engineer and that is non refundable. Absolutely outrageous.
These are the notes left by the second engineer as recorded on the plusnet site:
"pqt and eclipse test ok, t and d to mrs mellor. initial inst all of fibre had not been done correctly , internal wiring fr om nte was not up to standard so reconfi gured it to provide service pqt and eclipse test ok, t and d to mrs mellor. initial install of fibre had not been done correctly, internal wiring from nte was not up to standard so reconfigured it to provide service TIME:18-01-2013 11:23:08"

[#2]

I'm sorry to hear about the issues you've had here.
I've had a look at some of the previous notes made by my colleagues about this issue and fear a level of misunderstanding may have occurred. Where as our suppliers would charge us for such a visit, its up to ourselves to pass that charge on to the customer. In your case I can't see why we'd want to do that when in full understanding of what's occurred with your sockets and internal wiring being changed in such a way.
Leave this with me for now and I'll see what needs to be done to arrange another visit.
Adam