Is the history of Blackburn you’re referring to William Alexander Abram, _A History of Blackburn, Town and Parish_ (Blackburn, 1877)? That has a useful account of the Chew family in Blackburn, which seems very accurate where I’ve been able to verify the details. It’s online at http://www.archive.org/stream/historyofblackbu00abrauoft#pag...
I agree that the name Obadiah might suggest a family relationship, and that this is worth pursuing, but it might be purely coincidental. In the case of the earlier Obadiah, at least, as an Old Testament Biblical name, it must reflect the fact that the family were nonconformists. Several of that Obadiah’s children are recorded in the registers of the Particular Baptists in Blackburn. And the name Chew has its main concentration in the Blackburn area. (By the way, the wife of the plasterer Obadiah Chew is recorded as Ann Wardley, for reasons I don’t understand, in one of the member-submitted entries in the IGI. The extracted, and therefore probably more reliable, entry for birth of one of the children in the IGI gives Ann Robinson as her maiden name.)
No, I have no personal relationship that I know of with any of the Blackburn Chews: my own Chew family was from Northamptonshire.