Sorry, but God sent him the gospel that he might believe in Christ and, as a result, be saved.Thats why God sent him the Gospel to inform him of who saved him. We know he was already saved and had faith in the True God, and worked righteousness. No man can do righteousness as he did unless born of God 1 Jn 2 29
If ye know that he is righteous, ye know that every one that doeth righteousness is born of him.
Cornelius worked righteousness before he ever met Peter with the Gospel #1 Acts 10:2,4
A devout man, and one that feared God with all his house, which gave much alms to the people, and prayed to God alway.
And when he looked on him, he was afraid, and said, What is it, Lord? And he said unto him, Thy prayers and thine alms are come up for a memorial before God.
#2 Acts 10:34,35
34 Then Peter opened his mouth, and said, Of a truth I perceive that God is no respecter of persons:
35 But in every nation he that feareth him, and worketh righteousness, is accepted with him.
Acts 11:14 (NASB 95) — 14 and he will speak words to you by which you will be saved, you and all your household.’