The midfielder was expected to join Marseille on a permanent contract over the summer, but a failed move has seen him become a key part of an unbeaten Rangers side in the Championship.
"I've been delighted with Joey, it's the first time I've worked with him and he couldn't have done more," Sky Sports News quotes Redknapp as saying.
"He's been great on the training ground, great on the pitch on a Saturday and great off the pitch as well. He's a big part of the team at the moment."
QPR continue their bid for promotion on Saturday when they welcome Birmingham City to Loftus Road.