Resolution:
You need to select the “EMS Client Baseline” feature during the installation process.

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To select an item, enter its number. Enter '0' when you are finished. 3
 
   1. [X] 1)  Development
   2. [X] 2)  Server
   3. [X] 3)  Client
 
Do you want to customize the install feature selections? [Yes] n
 
Selected Installation Profile(s)
--------------------------------
   1)  Development
   2)  Server
   3)  Client
 
Product Feature Selections
--------------------------
   TIBCO EMS 8.0.0
      [X] EMS Server Baseline
      [X] Development Kit
      [X] EMS Client Baseline   <=== HERE
      [X] EMS Source
      [ ] Hibernate (For Database Stores)
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After installation, the tibemsadmin tool is missing from the bin directory.