I mailed in a $5,000 money order to Amex in CA. USPS is delaying the delivery. Bill is do tomorrow, will just paying the minimum due on a business account affect my credit or credibility with Amex in any way?
I know the answer is no longer relevent for you, but might be for someone else.
Pay the minimum so you don't get 'late fees'.
You'll be charged interest on the rest of the unpaid bill.
You can call and explain and try to get the interest waived. A call might even get the late fee reversed if you haven't paid the minimum.