The ex-club supremo hit out at Los Blancos for their treatment of the striker, and was particularly critical of Florentino Perez for going against the 34-year-old's wishes
The former Spain forward chose to depart the Santiago Bernabeu after falling down the pecking order, but Calderon claimed that the attacker had been the victim of a witch-hunt among members of club management.
"Raul is Spanish and was described as emotionally cold, but had to be at a German club to demonstrate his warmth and affection," Calderon wrote on his official website.
"[Some at the club] claimed he had the sensitivity of a cockroach without realising that Real Madrid would never really forget a legendary player who gave his life to the club since the age of 17, before scoring 323 goals to become the top scorer and highest appearance holder with 741 in the history of Real Madrid.
"His farewell was held in the purest sense of the word, at noon, but it resulted in a false and feigned embrace of the president [Florentino Perez] which could be seen as a small but sharp knife stabbing in the back of the player.
"Few know that the coach [Jose Mourinho] wanted to keep the player for another season. The Santiago Bernabeu was a silent witness of a few words of the president to his representative which effectively settled the issue and aborted the wishes of both [Raul and Mourinho]."
Raul is set to move on again at the end of the season after previously announcing that he will leave the Gelsenkirchen side over the summer.