Ten years ago Data Model Designer was a great software. Its algorithms dealt with the original Relational Model, as described by Codd and others more than 30 years ago. In the early 90’s that was what was available to the market (Oracle 6, DB2 V2.x, etc.). The diagnostics were appropriate.
All softwares based on Data Model Designer (DB-Examiner, ERWin Examiner, Data Model Analyzer) use the same algorithms I developed more than 20 years ago, with minor changes. Mr. Gabe O'Neill lacks the theoretical background ("fckng puritanism", according to Paul T. Sterbutzel) to define any new algorithms.
The diagnostics (basically, the goal of the software) have not been updated to recognize neither data warehouses nor O-O databases. Even upgrades on the Relational model, like triggers, are not diagnosed. If you try to run them on any of these models you will get all sort of illogical messages, some of those risky to follow without harms to your database.
Last, but not least, a tool that is supposed to diagnose your database should report all possible problems or not diagnose anything at all. It is a matter of trust. You should ask the sales person: what DB-Examiner does NOT diagnose? You cannot possibly say "My database is OK" if the tool you use to diagnose it fails to report severe problems it may exist. Ask them and see what kind of answer do you get.