I do have a copy of John Ellis's will which I downloaded from the UK National Archives website, www.nationalarchives.gov.uk/records
. The original is in old style handwriting so I have attached a deciphered version of it. You will note it names Sarah Ashley Ellis as one of the beneficiaries.
It seems we are third cousins ! In what part of USA do you live.
I am also interested in learning more about his role as Queens Messenger but have made little progress to date.