It is permissible for the workplace to deduct something from the employee’s salary to pay off a debt that he owes to them, provided that that is done with the consent of both parties and provided that it will not add up to more than what is owed.

Discount coupons which are obtained in return for payment are prohibited because they involve several infractions of Islamic teachings. Free coupons that are offered to purchasers without them having to pay anything in return are permissible and there is nothing wrong with using them and benefitting from them.

These instructions to prevent someone from attending the funeral of the deceased or praying for him, and the like, do not come under the heading of wasiyyah as it is known in Islamic teachings, which must be carried out. Rather they are more akin to sin and severing ties of kinship, as may be understood from the question. The deceased has no right to do that and there is no interest to be served by it, in addition to what it involves of depriving the deceased of supplication for him and prayers for his forgiveness. All of that is prohibited.