Every withholder shall be liable for amounts required to be deducted and withheld by the Withholding Tax Act regardless of whether the amounts were in fact deducted and withheld, except that:
A. if the withholder fails to deduct and withhold the required amounts and if the tax against which the required amounts would have been credited is paid, the withholder shall not be liable for those amounts not deducted and withheld; or
B. if the withholder's failure to deduct and withhold the required amounts was due to reasonable cause, the withholder shall not be liable for amounts not deducted and withheld.