I have two survival curves/functions given by two sets of data points

(t1, P(T>t1)), (t2, P(T>t2) ), ..., (tn, P(T>tn) )

(t1, P*(T>t1)), (t2, P*(T>t2) ), ..., (tn, P*(T>tn) )

where the time points are t1, t2, ..., tn and for each time point I have an estimated probability of survival until that data point.

The first survival curve, P(T>t), is estimated using a Kaplan-Meier estimator for multiple subjects/observations.

The second survival curve, P*(T>t), is estimated using a machine learning method and it models the survival for a single subject.

I am now in need to compare the two survival curves and ascertain whether there is a significant difference between the two. My situation is just very peculiar since I am dealing with a survival curve for a group of subjects vs a survival curve for one subject. Traditionally you would have two survival curves for different groups (eg male and female) and then you could check if they are different using a log-rank test.

I'm quite stuck so any ideas/references would be highly appreciated.

Thanks in advance.