Fiber laser etching Bambu matte PLA charcoal

I have had good result fiber laser (30w) etching Elegoo PLA Pro black, which gets about 80% white. But I’m struggling with Bambu Matte PLA charcoal, the closest I’ve gotten so far is about 40% white. It could be that the composition of Bambu matte PLA just can’t remove that much pigment additive.

Has anyone gotten better result than mine?