Looking at those road closures it may still be possible. The actual mileage to visit the locations is quite small, about 400 k so you have make up a further 1200 anyway. Khancoban to Cabramurra is out so that would require you retracing your steps from the Jindabyne end after going to Murray1 and 2 and the town of Khancoban using the Alpine Way which is open,Then back through Jindi and up to Adaminaby for the top of the hill and over to Cabramurra. I doubt that will be closed as that is the only way left into the town. So once there you can access the power station gate that is in the town itself and from there it will depend on whether you can access the few k of the Elliot way you need to reach the power station below the town and again there is no other way so it may be worth checking out. The other towns and power station are accessed off the snowy Hwy which is open.