"He didn't really go to the water, he was not a good swimmer. I'm not sure what happened."
He said he had spoken to Mr Palani's friends but it appeared he was alone at the time, and called the accident a "mystery".
Cousins Kelly McKay, 15, and Payge Olds, 16, helped to rescue Mr Palani from the water.
Last week, Payge spoke of her and Kelly's efforts to rescue Mr Palani, for which they were hailed by police as heroes.
"No one else was jumping in so I just thought, you know what, I am just going to step up and do it because we just need to help this guy before it's too late," Payge said.
Today Kelly said Mr Kathiresan had thanked her for her and her cousin's support.
She said she would still "love" to chat to Mr Palani's family.
Mr Kathiresan has now set up a Facebook page in support of the family, and was calling for donations to see Mr Palani's body returned home.
"Their family situation is worse than it appears, none of his family members hold a passport to travel immediately, nor do they hold funds to cover travel expenses. And Easter holidays has further complicated their efforts to even to try to be here with their beloved son during his final moments."
A statement on the page said friends and family were devastated by the news of Mr Palani's death.
"What makes this whole thing heart-wrenching is the fact that it took three days to identify him and to be notified to his family members in India.
"His family members were devastated to hear the news about their beloved son/brother, and they could not digest the fact that they were living a normal life for those three days without knowing that their son is fighting for his life miles across."
Kelly said she would like to see enough money raised to see Mr Palani's body returned home.
"I feel for them - it's just awful how the family didn't know about it for three days as he was unidentified. Knowing that he can't get back to India because they have no money is heartbreaking. It truly is."