As one other person appropriately pointed out in this thread the OP's question is moot because SDC does not allow co-terminals. Therefore by the book the request will be denied.
It doesn't matter what UA considers co-terminal airports under the "NYC" code. In theory all three qualify.
The OP should hope for IROPS to change their flight. SFO usually has a morning fog problem, especially with earlier departures.
-RM