You can get all known file names from a listfile. This is a simple list of file paths that most casc file programs use to locate file data.
You can get a usually updated listfile here:
https://raw.githubusercontent.com/wo...r/listfile.txt
(
that is a large text file, rightclick and select "save link as" to download it instead of viewing it in browser)
I believe what you are looking for are these two:
sound/spells/spell_dr_glyphoforca_cast_01.ogg
sound/spells/spell_dr_glyphoforca_cast_02.ogg
You can use the following chat commands ingame to confirm these are the sounds:
/run PlaySoundFile("sound/spells/spell_dr_glyphoforca_cast_01.ogg")
/run PlaySoundFile("sound/spells/spell_dr_glyphoforca_cast_02.ogg")