>>> relies entirely on the cooperation of the croupier/dealer coupled with inconsistent printing/cutting of the pattern on the rear of the card?

AFAIK there wasn't overt cooperation with the dealer. Ivy gave the casino a set of rules he would play by if the casino hosted him. He brought a woman who was an expert in reading the miscut edges of the cards. The "cooperation" was that Ivy demanding the same set of cards (the ones his expert was able to read) were not allowed to be removed from play - that was one of his specific demands, the dealer was merely doing what he was told to do by the casino.

This is what gave him an edge and allowed him to retain it. By not letting the dealer/casino switch decks to one his expert couldn't read, the casino made the case he cheated. Even though, they took his action on the basis of the demands he made - so had Ivy lost a few million, the casino would be trumpeting that they beat one of the greatest card players. When they got took for a ton of money? Then, and only THEN it seems they refused to pay him and the court case ensued.