That many files might have missed it -- concentration fatigue is very real in those scenarios.
Few options depending upon what you want.
1) The big boy hacking method is to do a trace. Either as a result of pressing a button or along the same path as a graphical effect will be the audio you want, some will also follow channels in the audio hardware as whatever sends it the relevant channel the stream to play will necessarily have fetched it from the ROM somewhere along the path.
2) Your 1.7k files... corruption could be an option here. Corrupt one half of the file, then the other in another version. See which one breaks and repeat narrowing it down as you go.
3) If you just want a copy you might be able to nail any background audio (set volume to 0, disable channels in emulator, loop around silence, disable instruments*) and do a loopback audio to grab it while it plays without any background noise. Use in whatever fan game or video you like from there, harder to do more in this game with it though.
*If this game uses the SDAT sound format then chances are said ridiculous number of files came from a SSAR which usually have no names either. There is then also an outside chance the effect you want is in some kind of instrument library or standalone if you did not check those. This game is also ringing a bell for being an odd format or take on it for audio, we occasionally do see dual formats used though usually more for music in the outside format. Further outside chance that you did hear it but the effect as rendered in the game is a sped up version of an existing format.
3a) As above but rather than loop back audio it will probably appear in RAM at some point. Grab it from that if you can. You might also use same RAM grab to search the ROM (most of the time they are not compressed additionally or otherwise different).