Not only these small, but strategic islands do not belong to Iran, but the whole north shore of the straight of Hormuz was taken by Iran from Oman.
There was a time not long ago, when Iran controlled nothing of the straight.
Seems doable (of course just a layman with zero expertise) to secure at least the side of the Strait that is hugging the coasts of Oman / UAE to start with to allow ships through, gradually pushing back Iranian influence and control even further.