Well if the Jews were cut off from Him I could understand your point, but they're not. The Jew can come to Jesus still. The covenant still stands without the Mosaic system in place anymore. Why is this so hard to understand? Why would you assume it's broken if you don't think the same as you? God promised Abraham that ALL the nations of earth would be blessed through him. That happened. It happened exactly how/when/how/where He said it would. So you trying to insinuate that if you believe this then you're rejecting His everlasting covenant? This is not accurate and it's not the binary choice you're making it out to be. No I believe exactly what He says and that's why I believe the things I do.
I just don't follow your logic here. The only way YOUR view could be right, is if the Jew COULDN'T be saved through Jesus. The fact they CAN be saved, and it's the ONLY way ANYONE is saved, completely destroys this idea of separation between us and the Jews that you're trying to put on it. They were chosen by God. But chosen for what? To bring forth the Messiah. You have to add all the extra stuff to His word to believe otherwise.