"Would these scientists describe three DIFFERENT species?"
No.
"all from the same carbon dating period."
Carbon dating wasn't used here.
If I could be in a line of work where I could provide an answer such as "anywhere from 200,000 to 500,000 years old" in response to a question like "how old is this skeleton," and GET PAID for that answer, I would have a much less stressful life.
Sheesh.