There were six deaths, suspected to be drug-related, at a music festival organised by his company.
The shocking incident left him "heartbroken", said Mr Iqbal Ameer, chief executive officer of The Livescape Group.
The Malaysian music and creative events agency had staged the-three-day Future Music Festival Asia (FMFA) at Bukit Jalil Stadium, near Kuala Lumpur, in March.
Tragedy struck on March 14, the second night, with a suspected drug-related death after the showcase A State of Trance in the stadium.
Another five people who were at the festival died later from suspected drug overdoses. All six were Malaysians.
The Livescape Group cancelled the third night of the festival and was slammed by thousands of disappointed festival-goers, some of whom had travelled to Malaysia for the occasion.
An estimated 85,000 people would have attended the RM15 million (S$5.9 million) three-day festival.
Mr Iqbal, 28, told The New Paper last week: "We did a lot of work and put a lot of effort into it. What happened was way beyond our control.
"It could happen anywhere and it happens everywhere. For us, we had to lick our wounds, be better and stronger as well as learn from our experiences."
His friend, Mr Jason Kong, 30, who is also Livescape's public relations head, said: "To say that he was heartbroken is an understatement. In the time we have worked together, I have never seen him like he was that night.
"He was very strong but I knew it was only a front and only because he was the leader. But it hit him more than anyone."
Mr Kong said the company lost RM4 million as a result of cancelling the last night's event as they had to reimburse the affected acts and refund ticket-holders.
Mr Rudy De Rozario, the managing director of Singapore concert promoter Live! Empire, said the losses are considered small for such a large-scale festival.
"Considering the production costs, which can amount to a lot, as well as the quality of their acts, I had expected them to lose at least twice that amount. But any loss, $2 or $2 million, is still ultimately a loss," said the 38-year-old.
Grammy-winning acts such as US singer-producer Pharrell Williams, US hip-hop duo Macklemore & Ryan Lewis and Malaysian singer Yuna were slated to perform on the third day.
The overseas stars had arrived in Malaysia to find out the festival had been called off "in the interest of public safety" following advice from the authorities.
Fifteen foreigners and 14 Malaysians were arrested on site and 16 people were taken to hospital for suspected drug overdoses.
Mr Iqbal said his team had taken all necessary safety measures, including bag and security checks, a functioning trauma centre with medical personnel, police posts and plainclothes police officers on the festival grounds.
"To be honest, whatever we did then, we went above and beyond what any event organiser would have done for a party of that scale," he said.