It's naive to think that a Dispensationalist Bible would never have been published had it not been for the work of Cyrus Scofield. He was just one of a huge group at the time advocating this ideology. In 1878, the heavyweights of the American Dispensationalist Movement met at a conference in Niagara Falls, including Socfield, James H. Brooks, Charles Erdman, James Hudson Taylor, William Eugene Blackstone, and many others. There they presented the "Niagara Creed," their agenda and beliefs as follows:
“We believe that the world will not be converted during the present dispensation, but is fast ripening for judgment, while there will be a fearful apostasy in the professing Christian body; and hence that the Lord Jesus will come in person to introduce the millennial age, when Israel shall be restored to their own land, and the earth shall be full of the knowledge of the Lord; and that this personal and premillennial advent is the blessed hope set before us in the Gospel for which we should be constantly looking.”
It's not hard to see how the Jews sought to exploit the statement, "...Israel shall be restored to their own land." And I'm sure it was through the editorial slight of hand at Oxford University Press that it morphed over time into "The Jews shall be restored to Palestine" along with many other deceptions.
Cyrus Scolfield, like many of his fellow dispensationalists, was a very ambitious man, and I'm sure he was flattered by the attention that such a powerful man as Samuel Untermyer paid him--and never gave a second thought as to why this Jew, one of "The Chosen," was so interested in this Christian ideology.
The idea of publishing a Reference Bible to support dispensationalism was probably not original to Scofield, but he was the one with the vanity and ambition to take on such a project. Given the right financial inducements, I'm sure it wasn't difficult for Untermyer to get Scofield to do his bidding, including, and most importantly, signing over the copyright ownership to Oxford so that they would have ultimate control over the book and the movement long after the useful idiot was out of the picture.