Theres not really much evidence to support this BTW. A few media reports at the time because he didn't start the 1st game. But he started the 2nd and was in the side more or less until he was injured on international duty and missed 2 months. He then started as sub a few times, which is a cautious move most managers would make bringing back a star, especially when you can just bring in another galctico to replace him.
He then started games again, taken off a few times in 2nd half, finished others. Pretty similar treatment to his father figure Ancelotti. But 1 of them was loved and the other was disliked from the start, so you can see how that goes from experience. 2 months later, in January, Benitez was gone despite being top of the CL group and touching distance of 1st place in the league.
The media will manipulate any situation to sell a story and help push a narrative. And the Chinese whispers start and get out of hand. I've seen people suggest he refused to play him, which is just untrue.
Time will tell if they do indeed work together, but it doesn't help to feed rumours based on very little evidence. Even if they have had professional differences, it doesn't preclude them from ever working together again.
As I've always said, I try not to burn bridges, as you never know who your next boss will be.