An update for CS:GO recently made some bit of mess that crashed some servers requiring GOTV as a cheap fix or workarounds to fix them. As such sm_precache_particles before a player joins a map can crash the server.
You need to add a mapname_particles.txt (explained here). You did it completely wrong that does effectively nothing using mapname_manifest.txt under /particles/ when it should be mapname_particles.txt under /maps/.
You should update your map to correct this. The command being used is fine but servers will need to not whitelist the command to work around it making it more of a mess on themselves.