You may need to adjust for time dilation near the black hole. > means that the black hole and star formed separately and the black hole later captured the star

You may need to adjust for time dilation near the black hole. > means that the black hole and star formed separately and the black hole later captured the star? That's why they say triplet. It's not actually possible for it to capture it directly without involving a third object. The speed that the sun goes towards black hole is the exact same speed that it goes away from the black hole, the only way for it to be captured is for it to shed some speed into a third object. That's why they're having trouble with the scenarios "unlikely" because it's not easy to do that. Those types of capture is tend to produce extreme and very non-circular orbits. It's extraordinarily unlikely to capture a star and end up in a circular orbit.