Citrix-ADM 13.0 76.29 is noted to be using localhost IP to send Syslog traffic instead of ADM IP to external Syslog server. As a result, Citrix ADM is not able to send the Syslog traffic to Splunk server successfully as seen below.
A tcpdump on Citrix ADM also shows traffic is generated and sent using localhost as below.
ADM is using localhost IP to send syslog traffic, which is known issue NSADM-70074.