I think Australian pull-ups arguably could be dealt with as a completely separate progression series to pull-ups, for many people they are inappropriate cast as step 2. I also found step 1 way way too easy and useless as any kind of prep for step 2. You said you’ve got adjustable rings, so you need to play with the angles (standing almost) until you find one where you’re able to get only several good form reps out and then work from there to lower your upper body. Alternatively find something to place under the bar and rest your lower body on that so you only pull upper body. Practising dead hangs should help your grip.