Thanks for the in-depth analysis of the issues in using DNA.
As for matching the DNA, the technology is probably not there yet and the DNA, by itself, may not be sufficient.
As for DNA collection, I am sure that many constitutional issues will have to be hashed out. It may take decades.
My main point is to force the man who conceives the child to be responsible, at least financially, for that child.
This very discussion may cause someone to find another way to make that identification.
Thanks for staying with the real issues in your comment.