Hi,
Apologies for delay in response, If you want to monitor as extension you would need to download zip from https://www.appdynamics.com/community/exchange/extension/tibcoems-monitoring-extension/ and install as per above link under <Machineagent_install_dir>/monitors folder
https://docs.appdynamics.com/display/PRO42/Install+the+Standalone+Machine+Agent
For saas/on premise above extension metrics will show up metric browser in similar path section where you see hardware metrics, hope that information helps
If the target server is JVM you can try also installing java agent and configure as per docs and you would need define custom pojo rules if no out of box load discovered:
https://docs.appdynamics.com/display/PRO42/Tibco+ActiveMatrix+BusinessWorks+Service+Engine+Settings
https://docs.appdynamics.com/display/PRO42/Install+the+Java+Agent?src=search
https://docs.appdynamics.com/display/PRO42/POJO+Entry+Points?src=search