Redfearn revealed last week that they had expressed an interest in the 32-year-old Wembley hero after Cardiff, the club they sold him to last January, intimated they were looking to off-load him this January.
However, Revell played in the Bluebirds' FA Cup defeat to League One Shrewsbury on Sunday and any exit could be dependant on the arrival of more bodies.
Other Championship clubs are also understood to have shown interest in Revell.
And Redfearn said things are now out of the Millers' control.
"We're looking to bolster in that area. He's someone we would be interested in," the boss said.
"The bottom line is, we can only deal with what we can deal with.
"If Cardiff don't want to let Alex go, if clubs don't want to let players go, then that's fair enough. We've got other targets and other things we want to do.
"We've got to look at everything. I think there have been tentative enquiries without there being a firm enquiry.
"He's Cardiff City's player and we'd have to go through the front door and be right with Cardiff.
"I think we have got to
look at all of our options and look at the best fit.
"Alex Revell was popular
here, someone we know well but he is one of a few.
"When we do decide which is
the right one we have to go through the front door and do the right thing with
Cardiff.
"We have to do what's right. Again Alex is a top player and did great
for Rotherham and somebody that would be the type of player we are looking for."
In a poll of over 1,200 Millers Time readers, 52 per cent voted in favour of Revell returning to the New York Stadium.
