You have said, "I know that you have said the birth dates for both ladies and their husbands are identical, Regretably, conclusive identities are not established by birth dates, even though the dates may be identical. Identities in a situation such as you have created can only be established by the surnames of fathers."
This is utter and complete nonsense.
Once again I will tell you that the recorders of these records spelled the surnames as they decided these should be spelled. There is every possibilty that your direct ancestors here signed by mark. THEY, your revered ancestors, may have had no clue as to how to spell the surname, let alone their auditors. Indeed, you ancestor Ferdinandus^1 spelled it Van Sichelaer when he indentured himself to his De Weese master in 1653.
One of the things that you continually fail to grasp it that there is a major difference--particularly in genealogy--between official records and the long-after recollections of 'witnesses' who might impart their imperfect memories to anyone--most especially a Notary.
You would hang your hat on those self-interested. This is a major faux pas among real genealogists.