I think you are on the right track. In Wallace Hale's book - Early NB Probate Records is a listing for a Charles RICHARDS of (Long Reach) Greenwich who died in 1801 or late 1800. He didn't leave a will but his estate was passed to Thomas RICHARDS to administer. So it is likely that this Charles was Thomas' father or brother and Thomas likely would've had a son named after him.
Good luck,
Suzanne Lisson