I already said that Israel's disobedience, and their eventual fall, is because they fail to accept Jesus as their Messiah, and be water baptized, as their law commanded them to, in Acts 3:22-23, it stated clearly
22 For Moses truly said unto the fathers, A prophet shall the Lord your God raise up unto you of your brethren, like unto me; him shall ye hear in all things whatsoever he shall say unto you.
23 And it shall come to pass, that every soul, which will not hear that prophet, shall be destroyed from among the people.
You are trying to overly complicate the matter by trying to distinguish between "keeping the law in faith and keeping it according to works". You heard of the term "Occam razor" right?
The Law directed them to Jesus as their promised Messiah and they rejected him, that is not keeping the Law.