They'll deem it to be a conspiracy...
Sadly C14 dating is only a guide and cannot be the only requirement for dating.
The experts quoted know all that I suspect.
What is interesting to me is that Mohammed was meant to be illiterate and the scriptures were revealed without him reading them and yet there are passages which so closely resemble the Torah and the Bible that it points to either:
a) divine intervention or
b) him having had access to Jewish and Christian texts aurally
Have a read here scholar, this, and other articles do tend to support the fact that C14 decay is reliable, providing certain supporting criteria are met.
Didn't Islam split-off from Judaism, at one stage?
After the Ishmael thing?
Indeed it did. Which one was the legitimate heir was the source of all the stramash. Naughty old men and their concubines and infertile wives.
Usual stuff, then...
Yeah, but according to Muslim tradition, Muhammad himself was a Hanif and one of the descendants of Ishmael, son of Abraham (quote from the WIKI on Muhammad)