Carwashhair/...
You could always just try.
Just waltz in with a/the boarding pass!
Many years ago, I was with Ansett Global Rewards, (still feel bad about it-it was just about few days before they went kaput), I was travelling on a Reward Z class fare with GR, flying SQ Z (J really), and had access to the ADL (old international terminal at ADL airport), and then the SQ lounge at SIN.
You can only try.
If you find your tix does not mention VA at all, all the better, because at first glance, its all only related to *A. Seeing VA is not in *A.
My tix was booked with NZ, and NZ & SQ being full *A members, if all goes well, I will get my dream access to the SK lounge at SYDi.
If I get turned back, then its the temp KC lounge.
But I would certainly try the SK lounge first.
Of course, this is pure supposition, unless someone has tried it and comes on here to say it positively is possible. Access to SK lounge on VA J/C/D or NZ J/C/D while the KC lounge is out of bounds.
Laksa/mee rebus/beef rendang/chinese meat buns/shaio mai/... mmm