At this stage and as long as Australia don't change the legislation (it happens in some way or another every year.) his retirement age and the age at which he can claim his super is 65

Same for me.
Unfortunately, Aus is one of those place where you can't move your retirement income to another country and can only be used as a retirement vehicle. This is because (assuming he is an Australian citizen) he can return to Australia and claim social security benefits at any time.
There are a few things I would suggest he check:
a) Is there any insurance on his super policy? If so investigate if he is covered when o/s. In most cases, you are covered for a nominal period but then this ceases. Which means you may think you are covered and then go to claim but will be ineligible. And they NEVER refund the premiums deducted from his policy.

How many policies does he have? Wherever possible consolidate them to reduce the fees being deducted.
c) Also when consolidating choose a fund which offers an Early Release of Funds under ‘Compassionate Grounds’. This will be the only way he will be able to access his funds should something unexpected happens prior to retirement. I included the definitions below.
The APRA (Australian Prudential Regulation Authority) website quotes
Specified grounds for release
If you cannot gain early access to your superannuation benefits on severe financial hardship grounds, you may consider asking APRA to approve the release of some or all of your benefits on specified grounds.
There are only very limited circumstances where benefits may be released on specified grounds. These are defined in Regulations and cover expenses in respect of:
• medical treatment or transport for the member or his/her dependant where the treatment is necessary to treat a life threatening illness or injury, or to alleviate acute or chronic pain or acute or chronic mental disturbance, and where such treatment is not readily available through the public health system;
• to prevent foreclosure of a mortgage, or exercise of a power of sale over the member's principal place of residence;
• modifications to the family home and/or vehicle to meet the special needs of a disabled member or his/her disabled dependant; or
• palliative care or death, funeral, or burial expenses for a member or his/her dependant.
The legislation also allows APRA to assess applications for Early release of benefits where the circumstances are consistent with, or in direct relationship to, the specified grounds.
Release of benefits to members who meet the specified grounds objective test will still be subject to the governing rules of their fund. These also apply to superannuation savings held in Retirement Savings Accounts (RSAs).
*NB Whilst there is another Early release called ‘Financial Hardship’ if he is not in receipt of an eligible Australian social security benefit for 26 continuous weeks he will not be able to claim And will be a waste of time.
Hope this helps.
I know it’s a bit of any essay. Its hard to stop when I get on a role.
Cheers
Melannie