Deleting data from a table containing LOBs did not reduce the amount of data reported INTERNALLY by the table or database
@edze asked a great question. I've known that LOBs are stored separately from the table data (with a pointer referencing the storage location), but I didn't know specifically where they were stored.

While searching for more information on where LOB data is stored, I found the following links:

http://itknowledgeexchange.techtarget.com/sql-server/deleting-lob-data-and-shrinking-the-database/

The key take away here (focused on a database shrink) is the following:

Do the database deletion as normal. 
Then backup and restore the database. 
Then do the shrink, followed by rebuilding the clustered indexes in order to fix the fragmentation issue which the shrink will introduce.


https://social.msdn.microsoft.com/Forums/sqlserver/en-US/f80ad8c7-e6c9-4538-a89b-8d6727050b9c/release-space-used-after-sql-server-delete-in-rows-with-blob-varbinarymax-using-textimage-on?forum=sqldatabaseengine

Here the key is:


Rebuild the clustered indexes of the table.
Execute DBCC UPDATEUSAGE (0)


With this being Standard edition, a rebuild will require a LONG lock - but it looks like the only way to recover the space.