Watchtower's blood taboo stands or falls based on one thing: What is was required of the biblical Noah.
Humans in Noah's time had health needs like everyone else among ancients. The use of blood transplantation for medicinal remedy was widely practiced from antiquity. Hence if God did not want Noah to use blood for this purpose there was reason to tell Noah that as a matter of biblical record. But there is no biblical record of any such a thing. Based on the biblical record Noah was free to transplant blood (even from slaughtered animals!) for medicinal remedy.
- Ancient Blood Transplantation, and Noah
Watchtower's blood taboo could not be more wrong.