Here's a link our Patch Manager team shared about all the logs for SCCM - holy moly (): Log Files in System Center Configuration Manager 2012 · Herman Arnedo Mahr
This looks promising, though it's logged on the console side:
(Log Name) SmsAdminUI.log | (Description) Records information about the operation of the Configuration Manager console. | (Logged on) Computer that runs the Configuration Manager console |
This may also be useful on the server side:
(Log Name) Smsprov.log | (Description) Records activities performed by the SMS Provider. Configuration Manager console activities use the SMS provider. | (Logged on) Site server or site system server |
You might check those two logs out and see if either of them fit the bill (or check out the big list and see if you spot others).
