Do not eat anything you find already dead. You may give it to the foreigner residing in any of your towns, and they may eat it, or you may sell it to any other foreigner. But you are a people holy to the Lord your God. - Deut. 14:21
Of the five verses you referred to this is the only one that is interesting. The context is Moses' restating of the law following the wilderness years. This was 40 years after Leviticus. Most of Deuteronomy is copy-paste of Leviticus but there are some interesting differences and comments. Nothing that Moses says contradicts Leviticus but he does admonish the nation to be holy.
There were many ordinary things that resulted in uncleanness. Menstruation, skin disease, having sex with your wife, giving birth, burying a dead animal, eating an animal found already dead and more. None of these things were a crime or a sin but some were more avoidable than others. Moses identifies eating an animal found already dead as something that can reasonably be avoided in the interests of holiness.
Notice Moses' new instruction - "sell it to a foreigner". If the blood of an animal found already dead was sacred then this would be a very strange instruction. If the blood represented the life of the dead beast then it must be buried with the animal returning it to god.
Moses' instruction here is perfectly consistent with Lev.11 and Lev.17. The blood of an animal found already dead has no sacred significance since nobody took the life and therefore nobody can return it to god. The only issue is that eating the animal makes the person temporarily unclean. Leviticus gives permission to eat the animal with the proviso that the Israelite must bathe and change their garments. Forty years later Moses goes further and admonishes them to void unnecessary uncleanness and sell the carcass to a foreigner who was not under the law.
Blood was sacred insofar as it represented a life that had been taken by a human. If an animal died then its blood was of no significance. The only issue was the uncleanness that resulted from handling it or eating it. Uncleanness was not a sin but was to be avoided as far as practical. The only crime was to ignore the provision for cleansing.
Perhaps the Watchtower should issue new orders that it is necessary to have a bath and put on clean pyjamas after a blood transfusion.
