I have been able to identify some unknown file names in two TD MIXes - AUD.MIX and SCORES.MIX. Here they are:

Unknown files in AUD.MIX:

Filename ID Size Description
--------------------------------------------------------
cmptalk2.aud FA2D0EBD 15104 garbled speech
cmptalk3.aud FC2D0EBD 179208 garbled speech
cmptalk4.aud FE2D0EBD 123516 garbled speech
cmptalk5.aud 002D0EBD 98292 garbled speech
finish1.aud 81E00B00 14188 installation end

Unknown files in SCORES.MIX:

Filename ID Size Description
--------------------------------------------------------
nod_map1.aud 24070101 412245 Nod Map Theme
nod_win1.aud 24031115 372405 Nod Score Theme

While I have grabbed the file names for AUD.MIX from the DOS setup.exe, the Nod score and map themes' names were just a lucky shot. I have verified the names with Mix Manager and XCC MIX Editor, and they seem to be correct (are converted into correct IDs).