I misunderstood too! I thought you meant the parents of these chicks were from McMurray but I reread and understand now!Oh GOSH I’m blind I apologize!!! You’re so right, I accidentally included the wrong picture for the first one wow I’m sorry! xD
This chick could be a Black Australorp, Black Minorca, or White Faced Black Spanish! Give it some time to mature out and for body type/earlobe color to become apparent. 10-12 weeks old would be a great time for that!

