Filter Across Similar Fields only shows Field 1 values

Need some formula help --
4 Multi-Choice fields in same table: Company 1, Company 2, Company 3, Company 4.
Each of these 4 fields has the same set of Choices: Red, Blue, Green, Yellow.
Each record can have 0-4 Company fields filled in.
I need a filter to identify if any of the 4 fields has "Yellow", then filter will show word "Yellow". Or if any of the 4 has "Red", show the word "Red".

a. I created concatenated field Company1234 and then created a Formula Text field
If (Contains([Company1234, "Yellow")=true, "Yellow", Contains([Company1234, "Red")=true, "Red", Contains([Company1234, "Blue")=true, "Blue", Contains([Company1234, "Green")=true, "Green","")
Doesn't work the way I need it to - seems to only filter to show if Company 1 is the value.

b. I tried another Formula Text field 
If((Contains([Company 1], "Yellow")=true or Contains([Company 2, "Yellow")=true or Contains([Company 3], "Yellow")=true or Contains([Company 4], "Yellow")=true), "Yellow",
(Contains([Company 1], "Red")=true or Contains([Company 2, "Red")=true or Contains([Company 3], "Red")=true or Contains([Company 4], "Red")=true), "Red",    etc
This also filters if Company 1 has the value.

This is part of an older app which was setup as a large flat file and I am trying to create some filters to check data while I transition it to Parent Child structure.

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Ruby Kapil
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