ALDI Australia has this bike listed as forthcoming:
https://www.aldi.com.au/en/special-buys/special-buys-sat-7-september/saturday-detail-wk36/ps/p/premium-mountain-bike-1/

with a link to AMB mag for more details. However, I can't find on the site any indication which bike this is. I'm looking fto buy for my husband who's 6'2" - is the large frame option of this bike suitable? Is it suitable for 20min street riding (to work)? He already rides a falling-apart old thing and needs something new.

This isn't a performance mountain bike but for a 20 minute commute along paved roads or some light off-roading (fire trails) it''ll do the job just fine.

Review here.
https://www.ambmag.com.au/gallery/we-test-the-aldi-premium-29er-mountain-bike-529075

I'm 6'2" and I ride a large in the 'Giant' range.  He'll be fine with a large or XL.  There isn't a lot of difference. 

Thank you so much!

You're welcome.