A deed of family arrangement after someone dies intestate and letters of administration have already been granted?

Long story short. My mum owned a property and died without a will. Everyone knew she intended for the property to go to her kids, instead will go to step-father (below asset limit). He wants it to go to us whilst minimising the costs. Solicitor has said because the letters of administration are in his name a family agreement is impossible. Unsure if it's worth the expense of getting another opinion.

Long convoluted version:

To be clear it's 100% my step-dad pushing for the transfer.

My mother died without a will. Her sole asset was a property she had inherited and had intended to go to her kids (step-father was happy with this - they married later in life etc.) Because she died intestate it instead automatically goes to my step-father (it is under the limit).

Step-father saw a solicitor and the solicitor's advice was to to see an accountant and centrelink and to either get the letters of administration and come back or they could get them organised if that was easier.

We then went to the accountant together. The accountant mentioned that a legal agreement might be possible where technically it would never belong to my step-dad and could be transferred but to see the solicitor to check (googling it looks like he was talking about a deed of family agreement). Centrelink was around the aged pension and he's aware of all the options/impact there.

We then got the letters of administration in my step-dad's name.

We subsequently saw a different solicitor (step-dad's choice to change, this one was recommended by law society) hoping to get more info and to organise this. Instead their advice is that because my step-father has obtained the letters of administration that it is no longer possible for a deed of family arrangement to happen (Instead he needed to decline getting them and the next in line should have applied for the letters of administration) and instead we should go see a different accountant so they can help with how to minimise the CGT etc. and then go back if they think of anything.

I know I can't ask specific questions about if this is accurate and we would need to seek a second opinion. But it feels a bit like we are chasing our tails and keep getting somewhat contradictory (or at least incomplete) advice. We don't know if we're at a point where legally the only option is to transfer the property in the same way as a sale.

I understand that the bulk of this is probably on us for not following up/having them do everything/changing but the costs have been quite high (around $1000 for the two solicitors and accountant for about a combined hour of their time) which with the expense of the other costs made it seem sensible to handle as much as we could ourselves and obviously we didn't think we'd be screwing things up this badly.