Just over a week on, Marcia herself has shed new light on what caused her sudden collapse in an interview with The Daily Telegraph.
"I don't know what happened. I was about to go and do the semi-final for Australian Idol," she shared with the publication.
"I was in my dressing room with my godchildren and some good friends, and I had my makeup done."
"I was sitting down, stood up, and fell over. I had a urinary tract infection," she finally confirmed.
Returning to the judging panel the next day, Marcia told viewers that she felt "fine."
"I want to thank everyone who reached out towards me, you know. I do appreciate it. And you guys need to know - I couldn't have missed this for the world. I couldn't have."
The beloved entertainer went on to reveal that she had sustained a cut on her forehead that had required stitches and agreed with her doctor to return to the hospital after the winner of Australian Idol for 2024 had been revealed.
"I was able to talk to the doctor and say, 'Listen, I really need to go back to work. It's the final, and I'm really attached to these kids," the entertainer shared.
While her doctor "didn't feel comfortable with it", Marcia was able to use her powers of persuasion and re-admitted herself for several days of rest and cooperation after Australian Idol wrapped up.