If you work in HR, then you probably already know not to state your age on your resume, and to cut down your resume to show "Relevant Experience" not "Career History" - which allows you to cut out your early career history, so they can't calculate how old you are. Many Australian employers are ageist but it's illegal for them to ask your age - so make it hard for them to guess.
You're also up against the fact that the 482 visa is more expensive and more onerous on the employer than the old 457, so an employer is more likely to accept a less-qualified local candidate than go through all the hassle of hiring you.
I understand the desire to be close to family, but you should also consider that you'll need considerable funds to finance the parent visa when you ultimately apply for it, so it might make more sense to return to the UK where you could get a higher-paid, more secure job for the next few years and save up for the permanent move.
I wish you the best.