The cited 63% "relative" survival rate for T2 patients diagnosed 1988-2001 is (1) surely lower than the relative survival rate for T2 patients diagnosed in 2017, and (2) a generalized way to try to home in on the odds of dying specifically from BC (meaning that for that vintage of T2 patients more than 37% died within 5 years, if you include deaths from other causes), with that general adjustment not necessarily being accurate for all ages and other individual nuances. But it's a correlation, and correlation doesn't necessarily mean causation. For example, a large share of those diagnosed with BC in that period were heavy smokers. So to some extent, that 63% figure is saying "patients diagnosed with BC then were more likely than the general population to be heavy smokers, and heavy smokers were significantly less likely to survive their next five years than was the general population."
To see through that sort of confound, it would be good to be able to estimate an absolute rather than relative survival rate for an age-specific, stage-specific subset of BC diagnoses, and then compare it to the absolute survival rate for the same age in the general population.
As cited earlier in this thread,
www.cancer.net/cancer-types/bladder-cancer/statistics states that for muscle-invasive bladder cancer confined to the bladder (that is, for T2, excluding T3 and T4, and with N=0) the recent 5-year survival rate (which I read as the specific=absolute survival rate, not a "relative" rate) is 70%. The same article says that "the average age people are diagnosed with bladder cancer is 73." According to the Social Security actuarial table I cited earlier, about 18% of US males aged 73 will die within their next 5 years. (I get that by summing the table's yearly death percentages for ages 73, 74, 75, 76, and 77.) So as a crude adjustment, if we suppose hypothetically that all T2-diagnosed, other-stage-excluded patients are male and exactly 73 years old, these statistics seem to indicate that 30% die from something within 5 years, and 18% of them would die without MIBC, so 12% will die from BC. That is, to a first approximation 12% of T=2, N=0 MIBC victims die specifically from MIBC and most of those victims are considerably older than the OP's 42 years or my 54 years. On that basis, and assuming neither the OP or I turns out to have worse than the average T=2, N=0 condition, I have to think that with the greater general resiliency of younger patients (ability to tolerate dense-dose chemo, recovery from surgery, etc.) we each have a less than 12% chance of dying within 5 years and having the cause attributed to MIBC.
Also, with MIBC, there's not much difference between 5-year survival rates and 10- or 15-year survival rates; to a first approximation, if you last that long you're probably home free.