"I knew that -- I even knew that it was crazy that I was with somebody that I didn't meet," he told ESPN. "And that alone, people find out that this girl who died I was so invested in, and I didn't meet her as well."
Asked his response to those who say his son is a liar who "manipulated the truth, really for personal gain," Te'o's father gave a tearful reply, according to ABC.
"People can speculate about what they think he is. I've known him 21 years of his life, and he's not a liar. He's a kid," Te'o's father told Couric.
Questions have also been raised about Te'o telling Sports Illustrated in October that Kekua had attended one of his games, when he issued a statement last week saying he'd never met her.
Because ABC News has made public only snippets of the interview, it's not clear which parts of the hoax Te'o will address, but the Notre Dame standout has said he's sure he'll be vindicated.
"When (people) hear the facts, they'll know," Te'o told ESPN last week. "They'll know that there is no way that I could be part of this."
Nine days after the Alabama Crimson Tide dismantled the Fighting Irish in the college football national championship, Deadspin broke the story that Kekua didn't exist. The oft-irreverent sports news website has reported that a man named Ronaiah Tuiasosopo is involved in the scam and that he created a fake Twitter account for Kekua.
Deadspin's Timothy Burke, co-author of the story, said friends and relatives of Tuiasosopo's said he was "doing the Lennay Kekua fake online profile for several years and that he's caught other people in his trap, but that they caught on way earlier than Manti Te'o did."
Diane O'Meara, whose photo was used for the fake account, told NBC's "Today" show that she'd never spoken to Te'o but that Tuiasosopo called her to apologize.
"Ronaiah has called and not only confessed, but he has also apologized, but I don't think there's anything you could say to me that would fix this," she said.
Te'o, likewise, told ESPN that Tuiasosopo tweeted him after the Deadspin story broke, saying he was behind the hoax. He apologized, Te'o said.
"Two guys and a girl are responsible for the whole thing," Te'o said, according to ESPN.
An anonymous Notre Dame source told CNN the university's investigation yielded the same conclusion -- that two men and a woman perpetrated the hoax.
At least one of Tuiasosopo's relatives has defended him, though. His uncle told CNN, "It definitely takes two to tango," and, "This is not just a matter of blaming it all on Ronaiah." Tuiasosopo's father had no comment.
Burke said he isn't buying the notion that Te'o is innocent and emphasizes that Te'o and Tuiasosopo knew each other.
"How dense would Manti Te'o have to be to not realize this was his friend who was behind the account the entire time?" he asked. "I don't believe Manti Te'o could be that dumb."