Can you apply a tax directive issued to a different employer?

We have a temp employee that we would ordinarily deduct 25% tax. She has now come with a tax directive from SARS in the name of another employer that she also works for on a commission basis & ask us to apply the tax directive of 20%. Question:
1. Can my company apply this directive even if it is in the name of another company
2. Can my company apply this directive even if it is a photocopy & not the original

No, she needs to apply for a directive for you company and then present the original to you before you can reduce the percentage withheld.