Yes, he should have to.
The care of the kid comes before the circumstances of his/her conception. A father has responsibilities, no matter how he became a father (unfortunately). There are numerous cases of women stopping their birth control without telling their partners in order to have a child, and yes, those fathers also still have responsibility. Not to mention it’s incredibly unlikely and difficult to get the sperm to live long enough for in vitro (don’t most condoms have some spermicide in them anyways?). PLUS it’s impossible to prove that this man’s story is correct and he’s not just another ass trying to get out of child support.
But if the story is true, i feel bad for the guy.