If using the Management Pack in subject you may be experiencing issues with the discoveries related to the Central Administration Site (CAS) and Primary Sites.
You may think that those Discoveries don't work?
That's not in fact true…
Whilst the "typo" on the Management Pack Guide and other resources don't get updated a possible way of helping you to get it to work is telling you where to enable the Agent Proxy setting.
And that is on:
If not enabling Agent Proxy for the Health Service on the machines with those Site Roles you will also see 33333 events on the related Management Server as well.
Secondary Site Servers cannot have Agent Proxy enabled otherwise they won't ever get monitored.
You might need to override Microsoft.SystemCenter2012.ConfigurationManager.SiteSystemRolesDiscovery (Which targets Site System Information class hosted by the CAS to avoid it to timeout.
Default setting is: 300 seconds. Carefully override it in multiples of 30 seconds until it works.
Resuming: In the current MP Guide the highlighted text below should not be read.
For the Configuration Manager monitoring pack to discover objects, you must turn on Agent Proxy on every site server except for the primary site and the central administration site.
This was the Possible Way Of getting it to work and Hope This Helps!