"They told me they didn't think I'd ever walk again," one woman says sitting in a wheelchair.
"And I just said, 'no, no, this isn't how my story ends,'" she adds before she is seen a year later walking through the studio's doors holding onto the hand of her son.
Another woman is seen telling Karl that she "will die" and her "organs will shut down" if she doesn't lose weight.
While another guest tells him she is down to her "final six months" if she doesn't get a transplant.
The emotional scenes comes after a turbulent year for Karl who was sent packing after 14 years on the breakfast show by Nine bosses who were over the negative press surrounding his marriage breakdown with wife of 21 years, Cassandra Thorburn.
The second season of This Time Next Year was commissioned two months before Stefanovic's shock dismissal, at the time fans were convinced he'd lost the gig after he was caught "liking" a serious of scandalous Instagram comments which slammed Today producers for sacking him.
He was replaced by breakfast program hosts Georgie Gardner and Deborah Knight.