I ran into a glitch with the match PGN and will add it to the game scores of the other matches as soon as I can.
I took the Staunton - Harrwitz games from my page titled Howard Staunton's Tournament, Match, and Exhibition Record (1840-1866; Last updated 2001-06-16) and expanded the PGN headers before uploading the file. Having some extra time to spend on the Harrwitz match, I looked at what various web authorities had to say about the result.
- Daniel Harrwitz (wikipedia.org) 'He lost a match in England to Howard Staunton in 1846 at odds of a pawn and two moves.'
- The chess games of Howard Staunton (chessgames.com) No mention of the match in the short bio.
- The chess games of Daniel Harrwitz (chessgames.com) 'He played matches against Howard Staunton (+0, =0, -7) in 1846...'
That last quote, taking only the games without odds into consideration, is typical of other references. The comment section on the second link (Howard Staunton, page=4) has a long discussion from 2004 between GM Ray Keene, a Staunton biographer, and SBC (aka Batgirl), a serious collector of Paul Morphy material.
As for a written reference, the Staunton chapter in E.G.Winter's 'World Chess Champions' (Oxford, 1981), written by R.N.Coles, says that Staunton 'decisively trounced the younger master Daniel Harrwitz'. The summary of Staunton's career in an appendix lists three separate matches with total score of +12-9=1. In my previous post I said, 'It was a close match', taking the cumulative score during the match into account.