Hmm. Wall didn't have one perfect solution. Could have groups "Webber, Carnegie, Johnson, Lincoln" and "Jackson, Boston, Sacramento, Denver" OR could also have "Webber, Carnegie, Johnson, Jackson" and "Lincoln, Boston, Sacramento, Denver"

Both are Andrews and capital cities -- it's not one solution, which I feel you should have.

Lincoln nebraska is also a state capital

As James mentioned, the capitals and Andrews have a second solution if you exchange Jackson and Lincoln.

Yes boys, they're called "red herrings" and they are what makes the puzzle a puzzle and not something out of Highlights magazine.

bad puzzle for the same reason as others have mentioned. puzzles should have one solution (or it should accept both). This would be like doing a sudoku but then being judged as wrong when the author left multiple solutions as valid.