Despite handing Benitez a three-year deal in the summer and then backing him when parting ways with director of football Marcel Brands, the Merseyside club have now sacked him.
Benitez has paid the price for a poor run of form at Goodison Park which has seen the club flirting with the relegation battle in the Premier League.
Benitez sold Digne to Aston Villa earlier this month after falling out with the defender, and former Netherlands star De Jong thinks it cost the Spaniard the dressing room.
“You know when that happens right, inside of the dressing room you lose the dressing room”, De Jong said on beIN SPORTS.
“Because Digne was a loveable character.
“So when you do that to one of your best players….”
Everton will come up against Digne’s new club Aston Villa next weekend at Goodison Park and it remains to be seen who the Toffees have in the dugout when Steven Gerrard’s men arrive.