Lynn,
Going back to the possibility that Thomas Fozard's parents were George and Sarah (Scott), the thought occurred to me that there may simply have been some sort of error that Thomas was baptised George Thomas (as clearly he was always known as Thomas). I must confess that I had always assumed that the older George must have died before Thomas was born.
This woulds at least explain why no other likely prospects for his parents emerge and also (since they had a son Joseph) why Thomas's marriage was witnessed by a Joseph Fozard.
Gavin