Decision Table columns always have an explicit AND between them.
You would have to emulate OR yourself by clever construction (and duplication) of columns. For example
Brand SubProduct Location Action
ABC 11 Whatever
ABC 22 Duplicate "whatever" from above
ABC 33 Duplicate "whatever" from above
ABC YYY Duplicate "whatever" from above
You don't specify whether you're using XLS Decision Tables or Guided Decision Tables in the workbench.
If you're using Guided Decision Tables you can create a "BRL Condition Fragment" (New column->Show advanced options) and include the OR in that definition.