We reported yesterday that the singer and actor, who was brought up in Bearsden, was found dead in his US apartment in Minnesota, on August 11.
Police confirmed that there were no signs of intent or suspicious circumstances, but the cause of death is unknown at this stage while medical examinations continue.
A source has revealed to the Scottish Sun that Darius had been “really excited” at the prospect of a Pop Idol reunion.
It's believed he was set for a potential return to the UK in just weeks for the special show, being made by Thames TV.
Stars of the competition from across the globe have been invited back — as well as Queen singer Adam Lambert, who won American Idol.
Plans were being made for filming at the Criterion Theatre in London.
The pal told the Scottish Sun: “He was really excited about the reunion and was in talks with producers to appear on it. They were looking at getting filming started around the end of September.
“It was going to be an hour-and-a-half-long special hosted by Ant and Dec and full of nostalgia for the millions of Pop Idol fans.
“I spoke to Darius recently and he was in good spirits — he was his usual happy self.”
Simon Cowell, former Pop Idol judge, remembered Darius as "just a great person to be with” following the news of his death.
In a statement given to the PA news agency, the 62-year-old said: “I first saw Darius on television over 20 years ago and I got to know him really well.
“He was charismatic, funny and just a great person to be with."
Hundreds of others paid tribute to the star, who won hearts on the first series of the ITV talent show, coming third behind Will Young and Gareth Gates in 2002.
Gates said: "I can’t quite believe the news of my dear friend Darius passing. I’m heartbroken.
"Darius took me under his wing during our time in Pop Idol, like a big brother; always looking out for me and for that I thank you my friend.
"I will miss our chats. He was one of the most beautiful, intelligent and gentle souls I was lucky enough to know, a soul that lit up every room.
"Goodbye, my friend. Forever in my heart x"