Custom soundset not showing up in toolset

So I tried downloading these NWN2 voicesets:

I put the wav, ssf and soundset.2da files into override as instructed, and then the tlk file in the tlk directory. The demo module included with this download didn’t show any new voices however (I double checked and it does use the tlk file in module properties). I also tried editing my actual 2da file instead of doing it the override way, but that also doesn’t work. Is this simply no longer a supported method of installing soundsets, or…?

PS. I’m using Diamond/1.69 edition.