Here is one of the answers to the best of my ability.

Who witnessed these events?

3) Islam does not disupte Jesus(as)'s miracles. There are some things about his life that are not accepted though. Historical data, as your co-workers mentioned, does not however prove his miracles or that he is the messiah.

[The Day] when Allah will say, "O Jesus, Son of Mary, remember My favor upon you and upon your mother when I supported you with the Pure Spirit and you spoke to the people in the cradle and in maturity; and [remember] when I taught you writing and wisdom and the Torah and the Gospel; and when you designed from clay [what was] like the form of a bird with My permission, then you breathed into it, and it became a bird with My permission; and you healed the blind and the leper with My permission; and when you brought forth the dead with My permission; and when I restrained the Children of Israel from [killing] you when you came to them with clear proofs and those who disbelieved among them said, "This is not but obvious magic." (5,110)

The Quran states that he did mention a messenger to come after him.

And [mention] when Jesus, the son of Mary, said, "O children of Israel, indeed I am the messenger of Allah to you confirming what came before me of the Torah and bringing good tidings of a messenger to come after me, whose name is Ahmad." But when he came to them with clear evidences, they said, "This is obvious magic." (61,6)

Please provide evidence of your faith's claim that he is not, and who is?

The Quran corrects those who say that he is more than a prophet and messenger.

And [beware the Day] when Allah will say, "O Jesus, Son of Mary, did you say to the people, 'Take me and my mother as deities besides Allah?'" He will say, "Exalted are You! It was not for me to say that to which I have no right. If I had said it, You would have known it. You know what is within myself, and I do not know what is within Yourself. Indeed, it is You who is Knower of the unseen. (5,116)

And to warn those who say, "Allah has taken a son." They have no knowledge of it, nor had their fathers. Grave is the word that comes out of their mouths; they speak not except a lie.(5,4-5)