I know DNA testing is better. The blood type only disproves not proves. I was only explaining about Blood type testing.
I can also say with 100% certainty that the father can influence the kids blood type. There is a even a pregnacy problem when the mother has A type and Baby B type or the mother has Negative and the baby positive (I think its calls RF factor)
DNA testing is 99.9% accurate, It cannot for example always tell which brother is the father