Leeds have not signed a single player since the Football League’s emergency loan window opened last month and they have little over three weeks to take advantage of the market.
Umbers is effectively in control of the club in the absence of Leeds’ former president and disqualified owner Massimo Cellino.
Redfearn said: “I think the club understand. I’ve spoken to Andrew Umbers and I’ve given him a list again - a list of players who’ll do for us.
“There are good quality players out there and clubs wanting to offload them for different reasons. It’s a time when you can get players. I’m hoping we can get a couple across the line.
“We’re at full-stretch. I definitely think that and obviously we need cover.”