No, they only knew the Messiah was here. And as I said before it was not fully realized yet, but it is still Christ. Just as the OT Jews sacrificed animals to cover their sins which was looking forward to what? Was it Christ coming? Or was it even though they didn't fully understand it that Christ would come and be our sacrifice?
Isa 53:1 Who hath believed our report? and to whom is the arm of the LORD revealed?
Isa 53:2 For he shall grow up before him as a tender plant, and as a root out of a dry ground: he hath no form nor comeliness; and when we shall see him, there is no beauty that we should desire him.
Isa 53:3 He is despised and rejected of men; a man of sorrows, and acquainted with grief: and we hid as it were our faces from him; he was despised, and we esteemed him not.
Isa 53:4 Surely he hath borne our griefs, and carried our sorrows: yet we did esteem him stricken, smitten of God, and afflicted.
Isa 53:5 But he was wounded for our transgressions, he was bruised for our iniquities: the chastisement of our peace was upon him; and with his stripes we are healed.
What was David looking forward to? Was Christ crucified at that time?
Act 2:25 For David speaketh concerning him, I foresaw the Lord always before my face, for he is on my right hand, that I should not be moved:
Act 2:26 Therefore did my heart rejoice, and my tongue was glad; moreover also my flesh shall rest in hope:
Act 2:27 Because thou wilt not leave my soul in hell, neither wilt thou suffer thine Holy One to see corruption.
Act 2:28 Thou hast made known to me the ways of life; thou shalt make me full of joy with thy countenance.
Act 2:29 Men and brethren, let me freely speak unto you of the patriarch David, that he is both dead and buried, and his sepulchre is with us unto this day.
Act 2:30 Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne;
Act 2:31 He seeing this before spake of the resurrection of Christ, that his soul was not left in hell, neither his flesh did see corruption.