The rocker reveals he was approached and offered the gig "months ago", revealing he'll perform with his band in Washington, D.C. on 20 January (17).
"The promoters asked if I was available, and I said yes," Neil tells Billboard. "So we sent all of the band's passports to the Secret Service, so everybody can get in, and all of the crew people, not knowing who was winning. But we were already scheduled to play."
Fans of Trump thought they had spotted Neil at the Republican's third debate with Hillary Clinton in Las Vegas, but the rocker insists it was a lookalike greeting the now-president-elect.
"My mom called me, and said, 'I saw you shaking Donald Trump's hand!' (But) I wasn’t there...! The funny thing is I was invited to go and I just decided not to and watch it from home.
"I think just because there was a guy with long blonde hair from Las Vegas, it’s got to be Vince Neil, right?"
Meanwhile, Vince reveals he has no idea what songs he will perform at the inauguration, stating, "I don't know if the Republican Party says which songs to play and what not to do. It's a little ways out. I'll have more information as time goes on."
Trump's choice of performer is a little controversial considering Neil recently struck a deal to avoid time behind bars after he was charged with attacking a woman and pulling her to the ground by her hair.
His lawyers appeared in court on 19 October (16) and pleaded guilty on his behalf to misdemeanour battery. Neil will have to pay $1,000 (£809), spend six months on informal probation, and undergo impulse control counselling, according to TMZ.
The rock star confronted the woman as he left a casino with Nicolas Cage. The actor was filmed grappling with Neil after the incident outside the Aria Hotel. The woman also sued Neil for over $150,000 (£121,000). That case is pending.