Mt Buffalo - Dispersed bush camping

Hello,
Am planning on doing an overnight towards Rocky Creek and I know there's a designated (and fully booked) campsite there but would prefer to camp in the bush (leaving no trace, no fires and minimal damage to plants).
I remember in 2016 a ranger I bumped into told me it was fine to bush camp in the area and was wondering if this was still true?
Thanks in advance.
Am planning on doing an overnight towards Rocky Creek and I know there's a designated (and fully booked) campsite there but would prefer to camp in the bush (leaving no trace, no fires and minimal damage to plants).
I remember in 2016 a ranger I bumped into told me it was fine to bush camp in the area and was wondering if this was still true?
Thanks in advance.