On Thursday, Dutch newspaper De Telegraaf said Garmin's Tour de France riders Christian Vande Velde and David Zabriskie, and two more US cyclists on other teams, had agreed to give evidence of wrongdoing in exchange for suspended six-month bans.
"No 6 mos (months) suspensions have been given to any member of (Garmin-Sharp owner) Slipstream Sports. Today or at any future date," Vaughters wrote on his Twitter account prior to the fifth stage of the Tour on Thursday.
When asked by reporters if he had testified against seven-times Tour de France winner Armstrong, the former professional cyclist declined to comment.
Slipstream Sports later released a statement echoing Vaughters's comments.
"We can confirm that our team is entirely focused on the Tour and media reports of suspensions are untrue," the statement said.
"As we have always said, we expect that anyone in our organisation who is contacted by any anti-doping or government authority will be open and honest with that authority but at this moment, we - our organisation, our riders and our staff - are focused on the Tour de France."
Last month, the USADA unanimously recommended filing formal doping charges against Armstrong, who is now retired and denies any wrongdoing.
The USADA has at least 10 former team mates and colleagues of the American willing to testify that he used performance-enhancing drugs between 1999 and 2005, a letter posted online by the Washington Post said.
Following the De Telegraaf report, USADA chief Travis Tygart said in a statement: "No individual cases have been finalised, and any attempt to guess at whom potential witnesses might be only leads to inaccurate information being reported and subjects those named to unnecessary scrutiny, threats and intimidation."
Armstrong, who could be stripped of his seven Tour titles if found guilty, wrote on his Twitter account that he was the victim of a witch hunt.
"So, let me get this straight...come in and tell @usantidoping exactly what they wanted to hear in exchange for immunity, anonymity, and the opportunity to race the biggest event in cycling," he wrote.
"This is not about @usantidoping wanting to clean up cycling - rather it's just plain ol' selective prosecution that reeks of vendetta."
Armstrong's former team mate Levi Leipheimer was the third rider named in the report but the American was reluctant to give any details on his involvement in the case.
"I cannot comment, I'm here to ride my bike," the Omega Pharma-Quick Step rider told reporters.
BMC Racing Team's George Hincapie, the other rider identified, said: "I've always tried to do the right thing for my sport but I've got other things on my mind here."
International Cycling Union (UCI) president Pat McQuaid told Reuters there would be no comment on the matter.
All the riders mentioned by De Telegraaf were once team mates of Armstrong, who never rode for Garmin but raced for Motorola, Cofidis, Discovery Channel, U.S. Postal, Astana and RadioShack.
Vaughters rode with Armstrong at U.S. Postal before retiring and setting up the Slipstream Sports team with an emphasis on taking a strong stance against doping.
The team previously fired Danish rider Alex Rasmussen, who was banned on Wednesday for 18 months for violating the anti-doping 'whereabouts' rule.