Didn't you write the same, twice?
The first statement should be read as "what are the chances that this particular person got results this good?"
The second statement should be read as "out of all investors active in the market during this period, what are the chances that one of them got results this good?"
If I read you correctly, you calculated "how likely is it that someone gets these results?". But accounting for survivorship bias, shouldn't it be "how likely is it that someone gets these results?" ?
Maybe I'm reading something wrong here, if so I would be obliged if you could elaborate.