That's your choice Keg man
CX has extensive history flying in areas of ash clouds all over the world as it effects some part of our network somewhere most days.
Seems the proof of the pudding is in the eating and as of now not one single RR Trent in our 330 fleet has evidence if Ash ingestion after flying below the ash area in Oz.
Not that I'm saying QF were wrong, just that their risk assessment ( probably helped along by GE RR PW and your leasing companies ) decision was not to fly. QF's choice but at the end of the day it COST QF a lot of dollars to stay on the ground when it appears the ash models were correct and if anything very conservative.