|You can return only ONE answer, |
either MMN, or MSNJ or WC
So which answer to you want to give?
You could do a nested IF, something like:
=IF(COUNTIFS(Data!E:E,A4),"MMN",IF(COUNTIFS('Metro South'!E:E,A4),"MSNJ",IF(COUNTIFS('West Coast'!E:E,A4),"WC",""))))
Without knowing what it is your trying to do, not much more to offer.