If there was ever a nuclear war with Russia, what would the probability of the US missile silo crew surviving?

Zero. Here’s a map of probable targets in a nuclear exchange:

Those giant black blobs in Montana, North Dakota, and Wyoming are America’s ICBM fields, and they are the highest of high priorities for annihilation – even more than decapitating the government (because neutering it is just as effective).

America’s ICBM silos would be so saturated by nuclear detonations to deny the US a “second strike” capability that everyone in the area will be dead 10 times over.