At any point in history, was it possible for the Jews and Christians to have combined their efforts to change their Scriptures, considering the Qur’anic confirmation to the contrary?

The Qur’an confirms the authenticity of the written text of the Tawrat, Zabur, and Injeel (the Bible) and concurs with the fact that earlier Scriptures were never changed or tampered with. However, could this change have even been possible considering the fact that the Jews and Christians had fundamental disagreements? For the Jews, the Old Testament (Tawrat and Zabur) was very holy and therefore if the Christians tried to tamper with it, the Jews would hold fast to their unaltered versions of the Scriptures. Moreover, there were many copies already in circulation all over the world (for thousands of years) and every copy would have to be recalled and changed, which was impossible. We do not have any historical record of such a monumental task ever having been attempted. If the Jews tried to tamper with the New Testament (the Injeel), the Christians would have never permitted it since the Injeel was very sacred to them, and they would still have in their possession unaltered versions of the Injeel. Moreover, there were thousands of manuscripts of the Injeel already in circulation before the Qur’an was revealed (which have survived even until today and are in many museums of the world). The fact is that a Jewish-Christian plot to tamper with the previous Scriptures never happened in history. Nor did the Jews and the Christians agree to change their texts at any point considering they viewed their Scriptures to be very holy – the Revelation of Allah. Even if they had wanted to, they would not have been able to do it, since thousands of manuscripts of written Scriptures were in the hands on believers all over the world.