The vocal group were originally due to perform for guest judge (of sorts) Kathleen Williams, mum of David Walliams, who was sitting in for a late running Simon.
But the music mogul returned just before their audition to hear them belt out We Will Stand Together and it's something the guys are still over the moon about.
Vox Fortis' Elias said: "The fact that Simon came back just before we went on kind of made us feel like it was the right time for us.
"We wanted to get the realest and dare I say, harshest Judging and the fact than Simon had good things to say was probably the best news."
He went on to say of their audition: "The most exciting part was listening to the Judges comments. You have an idea and you feel so confidently about what you do as a group, but then to sing in front of all those people and have the Judges say what they did – it’s a dream come true."
Speaking to the official BGT website at ITV.com, bandmate Julius added: "Simon has the ability to create a group like Il Divo and the fact that we are doing something similar to that, he has the ability to change our lives.
"We recognised that and we wanted him to hear us. We can’t wait for him to hear us again later on."
Looking ahead to the live shows and potentially WINNING the series, Elias said it would be "a dream come true" to perform for the Queen at the Royal Variety Performance.
"It’s been the most unique, magical and surreal journey and I don’t feel like my feet have actually touched the ground since we started and I don’t intend for them to," he conduced.
Britain's Got Talent continues Saturday night on ITV with more auditions.