Perhaps the simplest way is to test for a string that does not match (that is: !~) a regex like /2$/ ... which looks for the digit 2 anchored to the right-hand side of the string ... or maybe /2\s*$/ which would permit zero-or-more whitespace characters following the 2.

Go ahead ... use more than one test in that if-statement ... Look for a string that does match one regexp, and that does not match another.   As long as what you write works well and is abundantly clear, you are good to go.