A pre-film drinks reception in a private lobby offered patrons a chance to talk to the players.
The evening also saw Boks prop Botha and fellow South African Diack describe their experiences of South African rugby in an interview with Ryan Constable.
A raffle included memorabilia signed by Pienaar. Following the movie, guests enjoyed tea and coffee and mingling with the players and fellow rugby fans.
All profits from ticket sales went to the IRFU Charitable Trust, Ulster Rugby's nominated charity.
The Trust, set up in 1978, has been helping players affected by life-changing injuries with the medical costs involved and by providing specialised equipment such as wheelchairs and lifting equipment.
Ulster and Ireland hooker Rory Best certainly agrees that it is a cause worth supporting.
"The Trust is Ulster's nominated charity and it does fantastic work in supporting players who have been seriously injured," he said.
His brother Simon added: "The work of the IRFU Charitable Trust means a lot to me, as having had to take early retirement due to medical reasons I can relate to those who have found themselves in a similar situation.
"As a professional I was fortunate enough to have the support that comes with that.
"I can only try to imagine how hard it must be for an amateur to adapt following a life-changing injury. This is where the work of the Charitable Trust helps."
Speaking prior to the event, Paddy Wallace said: "I'm very much looking forward to hearing BJ and Robbie (Diack) talk about their playing experiences in South Africa.
"Having had the pleasure of playing in South Africa, I can say that it is a passionate rugby nation, so I'm sure the guys will have some very interesting things to say for the guests."
By kind permission: Niall Crozier, Belfast Telegraph
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