You want to monitor People Soft Tuxedo with APM environment and looking for an extension or agent for this purpose.
Currently APM does not have agent or extension for for People Soft Tuxedo monitoring.
You have a couple of options which may help you to meet the People Soft Tuxedo monitoring requirements.
1- using APMIA snmp monitoring extension.
2- writing custom field pack/extension
Note: option 1 is fully supported by support team.