I haven't checked in on Ancestry for a while, so I apologize for the late response.
I date Thomas's (your 8 GGF) birth even a little earlier. He was involved in a land transaction in 1650, so he was probably 21 by then. This gives a birth date of before 1629. He was also identified in a probate in 1651 (as Thos. Appelgate Jr.) as owing a debt to the estate, which indicates he was an adult by then.
We don't have a good date for when the Applegates came to America. They were present by 1634 and that's the best we can get. So we can't say whether he was born in America or not with any certainty.