The nutrients in that mix might be counter-productive for the purposes of germination. I had a batch of A. phlebophylla seedlings that I killed (wilting, shrivelling, and dying pretty much as you describe) because I accidentally fertilised them.
Seeds in general, I reckon, are self-sufficient and have no need of additional nutrients. So I tend to avoid fertiliser at this stage, as a rule of thumb.
For potting on, once established, native potting mix from Bunnings gives good results.
Bunnings also sells coarse river sand for propagation, your best friend.
Here's what Simmons recommends (scanned pages with info here)
Seed growing mix:
3 parts washed or sterilised coarse river sand
1 part peat moss or aged crushed pine bark
or
3 parts perlite
1 part peat moss
Potting on mix:
3 parts coarse river sand
1 part peat moss or old milled bark
1 part loam or perlite
or
2 parts sand
1 part peat
1 part gravel with old manure or compost added
Cutting mixture:
3 parts coarse river sand
1 part peat moss or old crushed bark
1 part perlite
or a soil-less mix
3 parts perlite
1 part peat moss