What proofs that the Jerusalem church held the same belief of St. Paul with regard to the crucifixion and resurrection of Jesus?

Some critics of Christianity, (Muslims, for example), argue that though Saint Paul believed that Jesus was crucified and his crucifixion has a significance (that he redeems all people from the effects of the Fall) but that doesn't necessarily require that the Jerusalem church led by James and Peter, believed that Jesus was crucified and assuming that they did believe that Jesus was crucified, then that doesn't necessarily require that the Jerusalem church, believed that his crucifixion has a theological significance (atonement). How can we be assured that The Jerusalem church did believe that Jesus was crucified and his crucifixion has significance? Please Note: Answers should exclude any textual proofs from the Epistle of James.