Keane spent the first half of the season with Liverpool but returned to Spurs in the January transfer window.
Redknapp told the Daily Star: “Robbie doesn’t have anything to prove. He’s back at Tottenham now, it was part of his life and it didn’t work out at Liverpool for whatever reason.
“He’s back here now, he’s done great for us and helped us to push up the table to where we are.
“It’s a game of opinions. I can’t criticise Rafa for what he did, it’s his club and he picks the team.
“Rafa Benitez has made more right decisions than wrong, that’s for sure. He’s got a team that has only lost two games all year and he didn’t see Robbie as part of his plans.”