Hi,
In answer to your query, I have no record of who married William Watkins, but, will check your 2 options, Ann Pitt and Ann Butler.
Also you said you are a "decendant of Thomas WATKINS via Richard Kear WATKINS c1854", as Richard Kear Watkins is my Great Grandfather and his youngest son Albert is my Grandfather, who are your grand parents ?

Thanks,
Gary