I've made simple undub mod based on this instructions https://gbatemp.net/threads/how-to-undub-laytons-mystery-journey-katrielle-and-the-millionaires-conspiracy.561278/
Enjoy!
File list
Laytons Mystery Journey
Laytons Mystery Journey Katrielle and the Millionaires Conspiracy Deluxe Edition [0100FB700D224000][v0] (2.65 GB).nsz2.1 GB
Laytons Mystery Journey Katrielle and the Millionaires Conspiracy Deluxe Edition [0100FB700D224800][v65536] (0.02 GB).nsz14.7 MB