Good on you! Call him in and don't accept anything else then complete refund (and try to get costs for removing this rubbish out of him). Plus he recommended the fitter to you, so if he tries to put the blame on him tackle your supplier on that too.
The supplier will lie through his teeth now but I have the power in that I haven't paid a penny yet.
In your opinion, is it second grade?
Many thanks for your help.
Second Grade? Fire-wood!