As Souths prepare to face Newcastle at Accor Stadium on Sunday in what represents a birthday celebration for Jai Arrow, Bennett was unsure on when he would have his all-star backline back on deck.
Campbell Graham will mark his return from a calf strain against the Knights, while Cody Walker will be back at five-eighth next week against Canberra as he serves a one-game ban for kicking Penrith's Jack Cogger.
But the fitness of Mitchell, who hasn't played since round 11 as a result of a back injury which robbed him of a State of Origin berth, remains a mystery.
Mitchell overcame his back complaint but then picked up a calf injury in training last month.
"Latrell's the only really missing link at the moment in the backs," Bennett said on Saturday.
"Jack (Wighton) came back last week and was pretty good for us so hopefully we can settle down now and have a steady list of our good players on the paddock.
"It (Mitchell's return date) keeps changing on me, I asked (the medical team) this morning and they didn't give me the news I wanted to hear so it's certainly going to be another couple of weeks."
As he waits on Mitchell, Bennett has also made a significant change to his backline by dumping Jye Gray to the bench and naming Matt Dufty to start at fullback against the Knights.
Bennett has lost five-straight games against the Knights but is hopeful Souths (8-7) can seal a win for Arrow, who was diagnosed with motor neurone disease in May, to strengthen their hopes of a top-eight finish.
"It's a pretty special day for Jai, but we've also got a team of blokes here that want to play well and do well and seal the day for him," Bennett said.
"I can't speak highly enough of what people have done and we're going to make his future and the future of his family a lot more secure.
"With so much doubt in it going forward, he's never going to have to worry about where he's going to get his next dollar from."
