The Ten Commandments instilled in Adam.....broken and damaged by the fall, nevertheless still there.
And this is your justification for gomming up Romans 2:13-15 and destroying the continuity of the text?
13 for not the hearers of the law are just before God, but the doers of the law shall be justified:
14 (for when Gentiles that have not the law do by nature the things of the law, these, not having the law, are the law unto themselves;
15 in that they show the work of the law written in their hearts, their conscience bearing witness therewith, and their thoughts one with another accusing or else excusing them); Ro 2
This law was something that non-Jews didn't have to begin with. They weren't hearers of it, they had never had it before it was written on their hearts, and they were JUSTIFIED by doing it - the doers of the law shall be justified
...that theme being reiterated here:
25 For circumcision indeed profiteth, if thou be a doer of the law: but if thou be a transgressor of the law, thy circumcision is become uncircumcision.
,,,here:
26 If therefore the uncircumcision keep the ordinances of the law, shall not his uncircumcision be reckoned for circumcision?
...and here:
27 and shall not the uncircumcision which is by nature, if it fulfil the law, judge thee, who with the letter and circumcision art a transgressor of the law?
This is no 'moral law' that every human ever born has instilled in them. This is God fulfilling His promise to write His law in their hearts.