mmm, I see what you are saying. I may be wrong but I find female C. approximata tend to be red/russet tinged, P. laticostata more green/grey. The forewing makings are echoed on the costa and part of the hindwing in C. approximata, less so in P. laticostata. The abrupt upward pointing peak on the postmedial line is what I look for in female P. laticostata. This shot with the weird angle makes this ambiguous. I need to look at this again later.
https://inaturalist.ala.org.au/observations?taxon_id=355218 c.f. https://inaturalist.ala.org.au/observations/248178010 forewing see position sub-terminal dark patch, white wiggly line below part of post medial line, 2 black vertical dashes antemedial/medial line also irregular shape of that band compared to females of https://inaturalist.ala.org.au/observations?taxon_id=1004767