At its core, this is a broader discussion about customization within the CoH client files. There are a few different things that you can customize on the client end (you'll see them on your computer, but no one else will). Sounds are one of these. Texture files are another. This is all by design and it's how the VidiotMaps overlays work, too.
When the game goes looking for texture and sound files, before it looks in the PIGGs, it first checks for the "data" folder in your CoH installation directory. If it finds what it's looking for there, it won't bother looking in the PIGG files.
For example, if it wants to grab the citymap.texture file, and it finds that in \data\texture_library\MAPS\city\citymap.texture, it loads that texture without looking at the files in texMaps.pigg.
For sounds, the idea is the same, but the path name under \data needs to match the path name where the sound would be stored in the PIGGs.
For the periodic spine burst, I think you need to place a dummy .ogg file in \data\sound\Ogg\Powers\QuillExplo2.ogg