Sorry Mike: I should have checked the image more carefully. I'm glad you swiftly dispelled my confusion of the bride, E or "P" Brady, with the second witness, whose name looks to me like S. D. Erby.
One candidate is Sarah Dinah Erby, whose death was registered in the Islington district in 1849 Q4, when she was recorded as 76 years old (born 1772-73: about the same age as the short-lived Elizabeth Brady/Mingay). Née Barrow, Sarah married George Erby (c.1757-1842) in 1795 at St Giles without Cripplegate, in the City of London. His will was proved in the PCC in 1844. I haven't combed through it for signs of kinship with the Mingay family but I suspect Sarah was a friend of Elizabeth.
Best of luck with your continuing efforts to root out some of the misinformation now embedding itself across the
Internet.
David
