Kulula absolving themselves without proof

I booked a flight MN 619 for someone and it was scheduled to depart at 20:50 on Thurs 11th Oct 2018. The person arrived at 19:50 at OR Tambo and stood in the queue. She was then told that she cant board the plane as she was late. This is their terms and conditions "Domestic check-in opens 90 minutes prior to your scheduled departure time and closes 45 minutes before take-off for kulula flights and 45 minutes prior to departure for British Airways (operated by Comair) flights"

It is clear that she still had enough time. I then spoke to Tebogo Marakalala ( Customer Relations) via ********** whose first reply without any proper investigation was "Thank you for the below. Mpho, we will never deny a customer to travel on their booked flight unless the flight is fully booked, cancelled or the customer is late for their flight. I was able to view Ms Shoba’s flight and it was not overbooked or cancelled. When a flight is missed, the booking has to be changed so the customer can travel on the next available flight. Changing a booking means a change of booking fee plus the difference in fares has to be paid. It is unfortunate that these fees have to be paid in order for the customer to travel. To learn more about the terms and condition of Ms ,,,,,’s ticket, kindly follow the link below. https://www.kulula.com/manage-my-booking/flights/missed-flights Our aim has always been to make travelling with us as convenient and trouble-free as possible for all our travelers. I’m truly sorry Ms ..... missed her flight."

This is despite the lady helping her even said that the standby passenger was not allowed to board the plane. if there was still space then why was the standby also not allowed?

I then responded "It says check in closes 45min before time. If you check her arrival time and the flight departure time you will see that she arrived on time. More over, you are giving me a standard response without any investigations from your side. Please investigate and also advise me when I can view the cctv if you claim she arrived late."

Tebogo's response " I’m sorry that you feel that I gave you a standard response. You are correct, the flight closes 45minutes prior to departure. To view CCTV footage, kindly contact Airport’s Company South Africa for assistance."