This reminds me of an argument I wanted to posit to a JW some day.
Every year there are hundreds of JWs who end up getting a divorce. Some even cheat on their mate to make the divorce official in "Gods" eyes. They get DF'd marry the person they really wanted and six months later they get reinstated.
Why cant they treat the blood issue the way they treat marriage? Lets say I had a child and my child needed a blood transfusion to save her life. I as a "JW" would rather give her the needed blood and get DF'd for six months than watch her die. I would choose being symbolically blood guilty than truly blood guilty.