I opened a TAC case from Cisco.  Quote from Cisco: Prime Infrastructure now being part of the enterprise strategy at Cisco - we have our investment for enterprise products first and have a huge backlog on Data Center platforms With the huge backlog ...

It works for me.  I am running PI version 3.1.6.

Monitor / Monitoring Tools / Syslog Viewer -> Historic page, there are two filter funnel icon on the right, click on the top one then pick "All Devices".  I hope that is what you are looking for.  I opened a TAC case and it took Cisco a while to figu...