This is because TOR-Loot doesn't get their data from people who have run the flashpoint, they get it straight from Data mining the client.
So essentially, you'll have items that are in the programming, but bioware haven't released the items for loot drop or have removed them etc. So they don't actually drop, so the datamining will return a "No Source Found" for who ever it drops from.
Hope this answers your question.
Thank you for answering my question. This was driving me crazy as to why there were drops missing when i went to go look at loot drops.