For your Austrian trip to Hallstatt there is also another train:

It leaves Innsbruck at 11:35 a.m. with one stop (1 hour 20 minutes to wait) in Stainach-Irdning (Styria).

You will arrive in Hallstatt at 17:31 p.m.

The Link for the Austrian railway: HTTP://www.oebb.at/en/index.html

Best greetings from Austria Rene (Graz,Austria)