@ $55 AUS that is a steep price. Best price here (US) was directly from the mfg. It's $23.30 from them and $2 more on Amazon. The only thing comparable seems to be Crystalac, which was $20 for a half pint, and there are a lot less reviews of it. It pays to be unique! That may be cheap compared to the rest of the English speaking world, but is still about 2/3 what I paid for the body it will go on ;-)
I just ordered some General Finishes Dye Stain. It's water based, but has a binding agent in it so that it can be used with other water based products, and is also supposed to help control blotching. The mfg recommends putting it on bare wood, and not filling first. It looks to me like you may have done it the opposite way?