This is a little late of a reply however saw your post after researching some of the Whaddon records and thought I would comment with an answer to your query and for posterity.
As per usual with many family trees of this era, the tree you found seems to be another tree of a person trying to link to nobility with no source or evidence.
There is no such marriage that took place nor is the spouse of Edmond (Edward) Musselwhite of Downton Eleanor Eliza Norwood.
Whilst no marriage record exists for Edmond Musselwhite due to the Downton records starting in 1602, his spouse can be found mentioned in the will of his mother in law Agnes Shotter (Shuter) of Whaddon who died in 1612 and was wife of John Shotter of Whaddon. Therein she mentions her daughter Eleanor Musselwhite and whilst doesn't specifically state her to be the wife of Edmond, she leaves legacies to Edmond Musselwhite of Downton and his children William, Richard and Judith.
There is also no record of a birth of a Katherine to an Edmond, nor is Katherine mentioned as a living child in the above mentioned will.
From this it is clear that Eleanor Shotter (Shuter) is the wife of Edmond, which is also backed up by Eleanor's burial record with her being the only 'Eleanor' buried as the wife of a Musselwhite as well as the birth of their child Judith.
