You are mixing categories here.
Our innate knowledge of good and evil is enough to condemn us for our sin, but is totally insufficient to bring us salvation.
Abraham was saved by Grace through faith in God’s promises, not through the narrow out-of-context quote from Dort which would be in opposition to their sola gratia doctrine.
So you would argue, all people groups, over the last 2000 years, and infants, without directly knowing Christ, are going to perish … I can’t accept God works that way - he’s not willing that any should perish; some will, and a narrow number are created as ‘vessels for destruction’; but I would argue the vast number in humanity have access to salvation based on the work of Christ but not always a direct knowledge of this work - that’s where natural law comes in;
Again, I realize this is a minority position