Toll gate fiasco

On our way to my mother's funeral coming from Nelspruit, we stop to pay for the toll gate which is the most expensive toll gate in south Africa! My husband wanted to give his card to pay and was informed only a credit card or cash, explaining to the guy what our emergency was and we had proof to confirm we were simply just told to go back to the nearest town that is Waterval Boven(not sure what the new name is). We had to drive back draw cash and go back to the tollgate. We obviously arrived totally late for the funeral. I mean come on a debit card will have money in otherwise it will decline right? Well, they don't even listen unless it's a credit card!