Rabobank wanted to control him and to change his personality to a model dutch boy (like R. Gesink). Dekker was too flamboyant for them to handle, so they searched an excuse to lay him off. They invented some news about variabel blood values (all persons blood values are variabel by the way, test your values now and next week, they will differ...). The people/press appearently took it as 'abnormal' blood values (which was never the case).
After they dropped him from the Tour squad, the deed was done, Dekker was already searching for a new team at that point and contact was through lawyers. Then Rabobank finally got rid of the contract and paid him a big sum of money not to tell anything about the real reason to others. Why would they do that? Probably because Rabobank is afraid their image will be hurt when the public knows they just wanted to get rid of Dekker, and had no real reason.
After they dropped him from the Tour squad, the deed was done, Dekker was already searching for a new team at that point and contact was through lawyers. Then Rabobank finally got rid of the contract and paid him a big sum of money not to tell anything about the real reason to others. Why would they do that? Probably because Rabobank is afraid their image will be hurt when the public knows they just wanted to get rid of Dekker, and had no real reason.