بسم الله الرحمن الرحيم
1- The NT confirms that only Peter witnessed the crucifixion:
34 Jesus said unto him, Verily I say unto thee, That this night, before the cock crow, thou shalt deny me thrice.
35 Peter said unto him, Though I should die with thee, yet will I not deny thee. Likewise also said all the disciples.
73 And after a while came unto him they that stood by, and said to Peter, Surely thou also art one of them; for thy speech bewrayeth thee.
74 Then began he to curse and to swear, saying, I know not the man. And immediately the cock crew.
75 And Peter remembered the word of Jesus, which said unto him, Before the cock crow, thou shalt deny me thrice. And he went out, and wept bitterly.
Now as we clearly see, Peter did witness the so-called crucifixion event. He was present there. The only thing that saved him from death is his denial that he knew Jesus. Otherwise, he would've got crucified that night.
2- The Apocalypse of Peter was written and spoken by Peter himself:
"This is a book that used to be an official part of the canon of the bible, it formally had been an official part of the New Testament. It was included in the original "Muratorian canon", (as well as in the "Codex Claramontanus canon"), which are the two oldest known listings of the "canon", or the official books of the bible. At some point this particular final "apocalypse" book was dropped from being the official last book of the canon and was replaced by the apocalypse book "The Revelation of John".
It was written by the Apostle Peter, it is his third book. The exact same Apostle Peter that wrote the two "Letters of Peter" that are already now included in the bible. The favorite disciple of Jesus.
3- The quotes of Peter's Apocalypse that confirm Islam's claims: JESUS NEVER GOT CRUCIFIED!
Here are the fragments of his Apocalypse.
When he said those things, I SAW HIM SEEMINGLY BEING SEIZED BY THEM. And I said "What do I see, O LORD, THAT IS YOU YOURSELF WHOM THEY TAKE, AND THAT YOU ARE GRASPING ME? OR WHO IS THIS ONE, GLAD AND LAUGHING ON THE TREE? AND IS IT ANOTHER ONE WHOSE FEET AND HANDS THEY ARE STRIKING?"
THE SAVIOR SAID TO ME, "HE WHOM YOU SAW ON THE TREE, GLAD AND LAUGHING, THIS IS THE LIVING JESUS. BUT THIS ONE INTO WHOSE HANDS AND FEET THEY DRIVE THE NAILS IS HIS FLESHLY PART, WHICH IS THE SUBSTITUTE BEING PUT TO SHAME, THE ONE WHO CAME INTO BEING IN HIS LIKENESS. BUT LOOK AT HIM AND ME."
"THESE THINGS, THEN, WHICH YOU SAW YOU SHALL PRESENT TO THOSE OF ANOTHER RACE WHO ARE NOT OF THIS AGE" (the Arabs who then became Muslims)