I'm thinking there is a false dichotomy here. If Christianity is false it doesn't mean that atheism is true. Both Christianity and atheism could be false. Christianity being true only depends on the resurrection of Jesus, and that depends on how regularly dead bodies come back from the dead, how many stories we have about dead bodies coming back from the dead, and how many times we have had verified stories of dead bodies coming back from the dead.

There are certainly Jews who think that the events in the NT generally happened (e.g. Toledot Yeshu), Muslims who think that the events in the NT generally happened, but still think that Christianity is false. I mean, Christianity could be false and yet you might still end up in hell because Islam was the "true religion".