The commentator is now on the road to recovery, however, thanks to quick actions of his wife and daughter, and continued dedicated medical care.
Waddle is unable to remember the July 11 accident, but had got up from bed at around 2am on a hot night. "I assume I got out to have a drink of water because there was water on the table beside where they picked me up from."
Wife, Clare, and their daughter Emma, 20, heard a crash and found Waddle "out cold" on the lounge/dining room floor of their fifth-floor Waikiki holiday apartment. He had struck the back of his head on the table. Blood was seeping from his ear.
"I can't begin to imagine what they went through at that time of the night in a foreign country," Waddle said. "It was quite traumatic for them."
But they kept calm, placed him in the recovery position and summoned the emergency services. "My wife and my daughter were absolutely amazing."
He was taken by ambulance to Queen's Medical Center hospital, where he was in an out of consciousness for about 48 hours.
When he came around, the first thing Waddle saw was his eldest son, Chris, a 44-year-old police officer in the Nevada city of Reno, walk into his hospital room. "And I thought to myself, 'Hello, is it over?' I thought I was on borrowed time."
In his dazed state, he thought his son had been summoned to farewell him. In fact, he flown to Hawaii to help out.
Waddle, who said his treatment at the hospital was superb, was constantly monitored - undergoing MRI scans and being treated by occupational therapists. He didn't need surgery.
"I didn't do too much talking, which people think is quite strange for me, being a talker. And that even carried on when I came home. I think it was probably a self-confidence thing - you don't know what you're facing."
There was one uncertainty he didn't have to confront. "I had travel insurance - that is the best thing I ever did."
After 10 days in hospital Waddle was cleared to fly back to New Zealand.
He underwent a "very busy" therapy programme, including being treated at a rehabilitation centre for people with traumatic brain injury.
He had initially suffered severe headaches and fatigue, but they had lessened.
Particularly worrying was the temporary loss of vision in his left eye. But it came right about a month ago.
Waddle, who has called matches around the world during his 36-year broadcasting career, put his eyesight to the test earlier this week at Wellington's Basin Reserve during the Plunket Shield match between Wellington and Auckland.
"[I] sat up in the commentary box and thankfully I could see the ball in the outfield, and [moving] around I could follow it," he said.
"When you've got a dodgy eye [and] you're worried about being able to see a cricket ball, which is your life vocation - that is depressing. But the fact now that I can see, I can talk and I can move - I'm feeling almost back towards 100 [per cent]."
He returned to Radio Sport last week on a light schedule, including preparing highlights programmes. And he was "up and ready to go" to call the first test between New Zealand and the West Indies at the Basin Reserve starting December 1.
Waddle was still being treated for lingering effects of his concussion, including having lost his sense of taste and smell. He had not been allowed alcohol, and was only permitted caffeine a week ago. He had a cappuccino but "couldn't taste a thing".
Another side effect was being unable to hear in his right ear when he eats. "I go deaf. And then the moment I stop eating, my hearing's perfect."
Waddle said his long-term treatment was "a matter of listening to the experts and following what they say".
"I've got a newfound understanding of rugby players who undergo concussion. It's not a pleasant experience."
He had been on the Hawaiian holiday with his wife and daughter for just two days when he had his accident. "I owe them a decent holiday!"
