The Charlton board have internally promoted former FA technical director Reed, 53, to replace head coach Dowie, who was sacked on Monday after just 12 Premiership games this term with the Addicks bottom following a 3-2 loss at Wigan.
Varney felt the club had no choice but to dismiss former Crystal Palace boss Dowie following a an unprecedented review of Charlton’s set-up.
The two-week review, which took place with Dowie’s knowledge, included quizzing players and staff on the club’s recent fortunes.
And Varney concluded Charlton were certain to be relegated unless the club’s hierarchy acted swiftly by dismissing Dowie and promoting Reed from his role as Dowie’s assistant.
“This is not just about results,” said Varney, who revealed Dowie was axed in a phone call by chairman Richard Murray around 6pm on Monday .
“I think we have taken a very considered look at the football side and whether or not we might have won at Wigan, we would probably have come to the same decision,” he added.