She reportedly returned to the USA on Tuesday to clear her name of any connection to the shooting.
The 62-year-old Danley was in a relationship with Paddock for a few years, reportedly meeting while she worked as a hostess at a Reno, Nevada casino.
News that Paddock was the man responsible for killing 59 people and wounding more than 500 was shocking to Alarcon.
After first describing her as a "person of interest" in the aftermath of the massacre perpetrated by Paddock, Nevada Police have now completely cleared Danley of any connection to the crime. NBC says that Danley traveled to the Philippines on September 25 via Hong Kong.
She was married for more than 20 years to her second husband, Geary Danley, and the couple moved to Nevada when they retired, the New York Times reported.
"He was kind of quiet, but I just remembered him being a nice guy", said former California State Assembly Member Richard Alarcon, who attended John H. Francis Polytechnic High School with Paddock, and knew him since he was seven.
Mendoza said the abuse came when Danley would ask to use his casino card to make the purchase.
The search for Danley initially spanned several countries, with conflicting reports that she could have been in Japan or the Philippines at the time of the shooting.
Danley was originally called Stephen Paddock's roommate, but later identified as his live-in girlfriend.
Ms Danley is now in U.S. federal agents' custody, and investigators will want to know if she can shed any light on why Paddock carried out the worst mass shooting in recent United States history.
Paddock's motive for the worst shooting spree in modern American history remains unclear, but authorities hope Danley could have some answers.
Information from Marilou, who lived with Paddock for several years, could be the breakthrough authorities need.
A woman lights candles at a vigil on the Las Vegas strip following a mass shooting at the Route 91 Harvest Country Music Festival in Las Vegas on October 2, 2017.
Las Vegas Police said they would next provide an update on the investigation at 1 p.m. PT (1900 GMT).
Paddock is thought to have transferred the money days before the shooting.
Clark County Sheriff Joe Lombardo told reporters that he is "absolutely" confident detectives will be able to determine his motive.
Danley's boyfriend Stephen Paddock was the gunman.
Investigators say that the shooting rampage was meticulously planned and included specially modified weapons. Earlier reports said that Danley was expected to return to USA soil on Wednesday. Investigators then wanted to know who he knew, and did they know about the attack.