The SAS is a long way away. But 1st Commando Regiment and 2nd Commando Regiment and Clearance Diving Team One are local - and all are trained to do what’s needed.
Sorry, I thought Aussie Commandos were more Ranger than Delta. I know they did a lot of ops in the WOT.
Commandos do have a bit of a different job from the SAS in combat situations, but when it comes to anti-terror, they do basically the same job.
2nd Commando Regiment supplies one of Australia’s two Tactical Assault Groups. The SAS supplies the other. And those are the peak groups for this type of work.
Clearance Diving Team has the same type of training as well, primarily to operate on ships - but they can certainly do it on land if they need to.
And any other Commando group could do it if they had to - but you’d use one of the specialist groups if they’re available.
Snipers cannot hit them because they are behind glass. A bullet hitting glass will be deflected to a great degree or at least some degree. Maybe three could fire at the same time.
One bullet breaks the glass and maybe one of the next would get a clean path.
Other than that, breaking in, with flash bang grenades hoping to startle them just long enough to kill them sounds like the best chance.
On the other hand if that doesn’t work and they set off bombs they will kill the rescuers too.