Agnes Duckett was almost certainly not the Agnes who married William Keeney (b. ca. 1601 of the Great Migration). Perry Streeter indicated today that William Keeney and wife Agnes more likely came from Devonshire and their daughter Susannah was the one baptized at Ilfracombe, Devonshire, in 1627.
Furthermore, I just discovered that William Kynney (who married Agnes Duckett) was probably the Willm Kynny who had a son Willm baptized in 1628 at Lutterworth, Leicestershire, about 3 miles away from where he married Agnes Duckett. And then I found a burial record for William Kinney at Lutterworth on 24 February 1668. His wife Agnes was probably the Anne Kinney buried in 1658 (although there is also an Ann Kinny buried there in 1670).
Therefore, William Kinney (who married Agnes Duckett) probably has absolutely nothing to do with the immigrant William Keeney. So should we change the Agnes Duckett profile to Agnes Unknown? I wasn't able to find a marriage record for William Keene (and Agnes) of Devonshire who are almost certainly the immigrants.