The bird in question that has been possibly IDd as welsummer or brown leghorn could also very well be a Whiting true green. Out of the 3 that I got this year I had one that looked fairly similar to that. The other 2 Whiting true greens that I received looked just like regular red sex links (the red stars you ordered)as they feathered in and matured.
Have you identified which was your free exotic?
Have you identified which was your free exotic?