SYMPTOM:
Users might find that some logical tables have column object dependencies, but the references to these columns cannot be found out either directly in the table or in any schema objects that use the tables (such as attributes, facts, etc). This might be apparent when importing Strategy Object Manager package which includes logical tables without any of its dependents, and throw error messages such as:
The source manipulator found a missing dependency. Object: <Column id=xxxxxxx> is not found. A total of 1 object(s) need it, one of which is <Table Name>. Please turn on the log for more information.

The reference to the column being used in the column alias is present in the attribute as well as the logical table from which the form expression is derived.
When the column alias is changed, the reference within the logical table does not get updated, which leads to the dependency on the old column alias' column.
ACTION:
This issue has been addressed in Strategy Developer 10.4 Hotfix 3 and 10.7. Upgrade to any of those versions to take advantage of the fix.