Police eventually blew open the door and found the killer dead from a self-inflicted gunshot wound.
Lombardo added that Paddock fired over 200 rounds through the hotel room door at the security guard.
Paddock shot the unarmed Campos in the leg as he was moving toward the room outside in the hallway, The Daily Beast reported being told by Dave Hickey, president of the International Union, Security, Police and Fire Professionals of America. "I was just doing my job".
"Any one of us could have been in the position he was in", Rodriguez wrote.
Lombardo said that the explosive tannerite and 1,600 rounds of ammunition were found in Paddock's vehicle, repeatedly stressing that the shooting appeared to be well planned.
When asked why he thought Paddock stopped shooting at concertgoers, McMahill said Tuesday he believed Paddock's attention had been diverted as he fired at the security guard. "He gave our officers the key card for the room and then continued clearing rooms until he was ordered to go seek attention".
Police have not yet released a motive for the shooting, which killed 58 people and wounded close to 500, and said Wednesday night that there was no suicide note.
Campos first arrived on the 32nd floor by elevator as Paddock had blocked stairwell doors leading to the hallway outside of his room, Hickey said.
Lombardo also said he thought it was likely that Paddock had an accomplice, given the 23 rifles and piles of magazines in the room, the additional firearms in Paddock's homes, and the electronic devices recovered from his Mesquite house.
Lombardo praised Campos along with the other security guards who helped to locate the shooter.