I know Vendyl personally, and have been to his home near Ft. Worth. He says the late Lubavitcher Rebbe disuaded him from converting to Judaism, telling him he would have more influence as a 'Noahide'.
And I know several of the rabbis with whom Vendyl has studied or consulted, both in the US and in Israel. And I also personally know several of the other ex-Christian ministers who studied with Vendyl when they were trying to reconcile the Torah with the New Testament.
Vendyl used to deny his connection to Indiana Jones, but he's gotten older and the story has been endlessly repeated anyway, and now he seems to acknowledge a connection.
There are many personal witnesses to the improbable circumstances in his life.