Let's remember what we were discussing. Without the Trust Fund, ie without the interest, Social Security's revenue would have been insufficient to cover scheduled benefits.
At the time you were arguing that the Trust Fund doesn't exist, and now you are saying that the interest on the non-existent Trust Fund means Social Security is in surplus. Is that about right?
Social Security History
Summary-
So, to sum up:
1- Social Security was off-budget from 1935-1968;
2- On-budget from 1969-1985;
3- Off-budget from 1986-1990, for all purposes except computing the deficit;
4- Off-budget for all purposes since 1990.