Right-back Riether was handed a retrospective suspension after being found guilty of violent conduct having being caught on camera stamping on Manchester United's Adnan Januzaj during the Whites 3-1 defeat at Craven Cottage on November 2 and will miss the game at Anfield.
The Cottagers confirmed on Thursday afternoon that striker, Rodallega, will be missing for up to six weeks after suffering a muscle injury in his left leg during the 4-3 Capital One Cup defeat at Leicester City ten days ago.
Boss Martin Jol will wait on the fitness of central defender Brede Hangeland and attacking midfielder Bryan Ruiz, who have respective sciatic nerve and back problems, before naming his final squad.
The Cottagers currently sit in 16th place and are just two points clear of the relegation zone, but Jol does not feel any pressure going into the game against high-flying Liverpool.
He said: "I don't think you are under pressure against Liverpool or Manchester United. You are under pressure in your home games against teams who should lose points against us, for example Crystal Palace.
"We really felt some pressure (against them), not because of me but because of the result. We needed points and we managed to win that game. We played well."
He added: "We had a very difficult schedule. We have played most of the top teams in difficult away games. The only really inconsistent game was 1-1 against West Brom. We need a few surprise results and maybe we can start against Liverpool."