I think you meant TR4303 (not 4304). Traditionally, NetApp FAS storage systems are/were neither syslog server and nor it listens on UDP port 514. It simply forwards it over UDP 514. I don't know if this has changed but this is an interesting question and I don't dig in much on this topic usually. But, out of curiosity I started reading about it.
With Ontap 9 onwards, you can send audit-logs to syslog server over tls, but I don't think it mentions EMS event-logs (which trdaitionally follows the syslog standards).