So you worked backward from your understanding of JW teaching on "spirit" and assumed this meant they would object theologically to the possibility of scientists creating life?
Except you forgot to check if the WT actually teaches that scientists will never be able create life on theological grounds. Well the WT does not object to scientists creating life, in fact it says they may well do so. So the thread is based on a false premise.
Maybe it's true that other Christian creationists claim that scientists will never be able to create life because only God can do that. I wouldn't be surprised if that is the case, but JWs don't teach that.