Have you tried the Log Exporter for that purpose (sk122323)?
You would need to install the Check_Point_R80.10_Log_Exporter_T50_sk122323_FULL.tgz package first as far as I can see and then I would refer you to the most relevant section for you:
Splunk
It is recommended to use Check Point App for Splunk when exporting logs to Splunk server.
For more information about installation and deployment, please see the Check Point App for Splunk User Guide.
In addition, in order to configure an encrypted connection, do the following:
1. Generate server pem file:
cat syslogServer.crt syslogServer.key RootCA.pem > splunk.pem
2. Update the inputs.conf file on the Splunk server
vi /opt/splunk/etc/apps/search/local/inputs.conf
[SSL]
serverCert = /etc/ssl/my-certs/splunk.pem
sslPassword = <challenge password>
requireClientCert = true
[tcp-ssl://<port>]
index = <index>
3. Update the server.conf file on the Splunk server
vi /opt/splunk/etc/system/local/server.conf
[sslConfig]
sslRootCAPath = /etc/ssl/my-certs/RootCA.pem
4. Restart Splunk
/opt/splunk/bin/splunk restart
I hope this helps.