Authoritarian regimes absolutely hate capitulating to their opponents (or being percieved as doing so).
Bingo. Also, if they changed their stance now, it will be painfully obvious that the Jehovah's Witnesses who died for lack of a blood transfusion did so for no reason whatsoever, so that will never happen. They would rather have people continue to die than admit they were ever wrong.
It's a tragedy that in 2014 people are still dying based on an irrational fear of transfusions, dating to the time they were first being used and considered dangerous by the ignorant. People still think they are "following their conscience", when they would have followed their doctors advice if the Watchtower hadn't filled their heads with misinformation.