This isn't survivorship bias, just imperfect information being sufficient. Will anyone be alive at X date can ignore the dead from the population as irrelevant.
The second question if they are an unusually healthy or sick group doesn't need to look at the dead either. Only ~20 percent of 35 year old men live to 88. Having at least 7 men out of 24 reaching that age is already an long lived group, though not necessarily statistically significant.
Looking at the full numbers gives a more precise number, but 12 of 24 vs 7(+) making it to 88 doesn't change the result. Further, even if it was exactly 7 of 24 again the answer doesn't change.
The second question if they are an unusually healthy or sick group doesn't need to look at the dead either. Only ~20 percent of 35 year old men live to 88. Having at least 7 men out of 24 reaching that age is already an long lived group, though not necessarily statistically significant.
Looking at the full numbers gives a more precise number, but 12 of 24 vs 7(+) making it to 88 doesn't change the result. Further, even if it was exactly 7 of 24 again the answer doesn't change.