“They are scattered around in hundreds of wack-a-mole subterranean military bases throughout the 320,000 square miles of Iran’s mountain terrain.”
In other words, mostly out of the way.
All they have to do is periodically launch a drone or missile from one of them at a ship in the strait and it’s locked down.
And by the time your magic radar locates the makeshift launch site and retaliates they are long gone.