Didn't Jesus predict Muhammad as the Comforter (Paraclete)?
No. Jesus named the Helper: the Holy Spirit, who would be in the disciples and stay with them forever, and who came at Pentecost.
Read John 14-16 whole: the Helper is the Spirit of truth, the world cannot see him, he was already with the disciples and would be in them, he would glorify Jesus, and the disciples were to wait in Jerusalem for him. Every Greek manuscript reads parakletos.
16I will pray to the Father, and he will give you another Counselor, that he may be with you forever: 17the Spirit of truth, whom the world can’t receive, for it doesn’t see him and doesn’t know him. You know him, for he lives with you and will be in you.
John 14:16-17 (WEB) · context
26But the Counselor, the Holy Spirit, whom the Father will send in my name, will teach you all things, and will remind you of all that I said to you.
John 14:26 (WEB) · context
13However, when he, the Spirit of truth, has come, he will guide you into all truth, for he will not speak from himself; but whatever he hears, he will speak. He will declare to you things that are coming. 14He will glorify me, for he will take from what is mine and will declare it to you.
John 16:13-14 (WEB) · context
4Being assembled together with them, he commanded them, “Don’t depart from Jerusalem, but wait for the promise of the Father, which you heard from me. 5For John indeed baptized in water, but you will be baptized in the Holy Spirit not many days from now.”
Acts 1:4-5 (WEB) · context
Reason 8: Prophecy points to Jesus. The "Muhammad prophecies" do not.