Ah sorry I misread, I thought you had said the gospels agreed jesus died on the day of preparation for the passover.
The thing is, in mark jesus eats the passover meal with his disciples. However John claims Jesus was sentenced on the day of preparation
John 19:14 "It was the day of Preparation of the Passover; it was about noon.
“Here is your king,” Pilate said to the Jews. "
So unless you think it took them 18 hours to get around to crucifying him (that is 9am passover day), which certainly isn't indicated by john, the stories still don't match up. I think the important part here is that john's version not only leaves out the passover meal scene, but makes it impossible to happen. John's version does have a last supper, but it is much different than mark's passover meal scene; but I think you already know this.
The thing is, in mark jesus eats the passover meal with his disciples. However John claims Jesus was sentenced on the day of preparation
John 19:14 "It was the day of Preparation of the Passover; it was about noon.
“Here is your king,” Pilate said to the Jews. "
So unless you think it took them 18 hours to get around to crucifying him (that is 9am passover day), which certainly isn't indicated by john, the stories still don't match up. I think the important part here is that john's version not only leaves out the passover meal scene, but makes it impossible to happen. John's version does have a last supper, but it is much different than mark's passover meal scene; but I think you already know this.