Reread the report. It does not say a submarine fired a missile.
You're absolutely correct!
Here's what it does say:
the FBI had checked all their torpedo tubes and all their missile silos to make sure they had all the missiles on board that they had when they left port.
Here's what else it doesn't say. It doesn't say what type, or class of submarine it was. Your implication in post 121 is that it was a ballistic missile submarine. So far, we have a friend of a friend who said...which doesn't carry much weight at all.