If a creditor or any one of two or more joint creditors at any time directs the debtor to perform the debtor's obligations in a particular manner, the obligation is extinguished by performance in that manner even though the creditor does not receive the benefit of the performance.
Extinction When Directions Of Creditor Followed
Mont. Code Ann. § 28-1-1104, under Extinction of Obligation by Performance.
Mont. Code Ann. § 28-1-1104