Dear Kevin,
I realise that this must be quite a nuisance for you, and I do not mean to be argumentative, or a complete *ss.
But, if you are a professional, I hope you have the financial means to handle a batch of defective film, either by buying another box of HP5 or switch to a different manufacturer. After all, it's upon you as a entrepreneur to see to it that a job pays, even if setbacks occur.
I really hope things work out OK after all.
Best reagards