Further to my earlier suggestion that the underground bunker be moved up into the air under the dish.

The entrance could now be the backdoor to the dish complex and not the main base with the hanger.

That way when the Rebels go through the bunker entrance they could enter a service elevator taking them though up through a cliff and into the tower (like a mountain lift).

Once again forgive the crudity of this mockup.

Hopefully more skilled hands can do the concept more justice.

When the supporting structure for the dish collapses the Rebels would have a short time to descend and debris could litter the forest and possibly create injuries.