An engineer needs to troubleshoot the following issue:Incomplete Identities on authoritative sourceIs this a reasonable...

Yes, reviewing the All Source Activity report available in Search is a reasonable action when troubleshooting incomplete identities. This report provides an overview of activity related to source systems, including account aggregations, transformations, and data flow from the source to IdentityNow. By reviewing this report, engineers can identify potential issues such as failed aggregations, data errors, or problems with source connectivity that might be causing incomplete identities.

References:

SailPoint IdentityNow Source Activity Reports Documentation.

SailPoint IdentityNow Troubleshooting Aggregation and Source Issues Guide.