CCTV footage from the fourth day of the Durban Test showed Warner walking up the stairs to the players' dressing room, engaged in heated conversation with someone else.
It comes after footage was leaked of Warner being restrained by teammates as he yelled at de Kock in the stairwell after tea earlier this week.
Australia maintain that Warner was provoked by personal comments that de Kock made about his wife, but the Australia batsman has accepted the charges brought against him by match referee Jeff Crowe and is now one demerit point away from a ban.
Bad blood continues to overshadow the four-Test series between Australia and South Africa which resumes on Friday.
The video shows Warner walk past de Kock and say, "You "f--ing sook. have a look at you, you sook". I don't know how their team manager [Mohammed Moosajee] can hear from where he's sitting, but from where I was, which was right nearby the whole time, there was nothing we said that was inappropriate", Paine was quoted as saying by Cricbuzz.
South Africa player De Kock was also reported along with Warner for the incident.
De Kock can't be banned but he will also be burdened in the future by demerit points unless his team successfully appeal. "As far as I am aware we didn't get personal toward Quinton", Smith said in the post-match press conference.
"I'm not surprised (de Kock is challenging the charge); not bothered; it doesn't affect the way we're going to go about this Test".
"We were trying to make it an uncomfortable place for Quinton to bat, no doubt, but we didn't cross the line".
"When he gets the bit between the teeth he is one of the best cricketers in the world".