You can try looking in C:\Program Files\Quest Software\Diagnostic Server\Agent\log\config-audit.log, and search for the text "SQLAnalysisEnabled".
If the log hasn't been rotated out, here is an example of the whole log entry you should see:
28 Oct 2010 12:33:22,328 DEBUG [MessageListenerNotifier(Job#453729)] User: DOMAIN\user (ADMIN) at 192_168_1_79/2879 (HOSTNAME_domain_com)
Role: ADMIN
set configuration list
Message: <ADK.Message>
<ADK.Type>215</ADK.Type> <TypeAsString> SET_CONFIGURATION_LIST_REQUEST (215) </TypeAsString>
<ADK.Data>
<request-details includeAncestor="false" path="./monitoredEntityTemplate[starts-with(@type,"database/sqlserver")]" type="procedure">
<properties>
<property isAttribute="false" name="SQLAnalysisEnabled">true</property>
<property isAttribute="false" name="SQLAnalysisTraceType">ROWSET</property>
<property isAttribute="false" name="SQLAnalysisEvents">SP:Completed|SQL:StmtCompleted|SQL:BatchCompleted|RPC:Completed</property>
<property isAttribute="false" name="SQLAnalysisFilters" />
<property isAttribute="false" name="SQLAnalysisRowsReturned">200</property>
<property isAttribute="false" name="SQLAnalysisColumnPriorities">DURATION</property>
<property isAttribute="false" name="SQLAnalysisServerLocation" />
<property isAttribute="false" name="SQLAnalysisDSLocation" />
<property isAttribute="false" name="SQLAnalysisMaxSize">5</property>
<property isAttribute="false" name="SQLAnalysisTraceTime">900</property>
</properties>
</request-details>
</ADK.Data>
<ADK.Property name="username">DOMAIN\user</ADK.Property>
<ADK.Property name="Sender">DOMAIN\user (ADMIN) at 192_168_1_79/2879 (HOSTNAME_domain_com)</ADK.Property>
<ADK.Property name="SenderHost">HOSTNAME.domain.com</ADK.Property>
<ADK.Property name="role">ADMIN</ADK.Property>
<ADK.Property name="Locale">en_US</ADK.Property>
<ADK.Property name="SequenceNumber">402</ADK.Property>
</ADK.Message>
