Disembarked too little too late.

FlySAA, my wife was disembarked off of one of your flights for not having a Transit Visa for her 1.5 hour stopover in London (for which I struggle to find any info on) on the way to Amsterdam (which she had her Visa in order for), not when she checked in at 3pm, or when she had to go back to the checkin as her boarding pass for the Amsterdam flight had not been issued an hour later, but rather just before boarding the flight at 19:45, almost 5 hours later by a rude woman wearing a manager badge that would not give her name as my wife did not need to know her name according to her (the manageress). If we had been informed by the first two people, who both had told her that ALL her paperwork was in order, we could have contacted the travel agent and sorted it out, only to have her in tears at the SAA counter at 20:03 and told cannot help you, you will have to wait till tomorrow!! The service is unacceptable and led to her being disembarked at a time where nothing could be done, no one taking responsibility, terrible service the first two times through checkin!!! Now we are stuck with having purchased a ticket through KLM as on Saturday, no one could help when the lines were open!!!! We are not impressed and no one wants to talk to us about options or anything, wasted a full 24 hours that it took for us to find another flight for her so that the accommodation was not wasted, what is your response?