N> How can one assert absolutely who misjudges or if anyone does?
Diana was the one who wrote of a misjudgment, so I cannot address that.
As to the Eugenides lines themselves, I don't think, as Diana states, that they are there to show that "Eugenides has to adopt new personae as he travels around from culture to culture". As I discussed last year, in my reading, Eugenides is a homosexual rapist who sexually assaults the narrator.
1) The Eugenides lines are sandwiched between a description of the rape of Philomela and the rape of the typist.
2) As Southam says, the Metropole is a "fashionable luxury hotel at Brighton, on the south coast of England, sixty miles from London. A 'week-end at Brighton' is understood colloquially as an invitation carrying sexual implications."
3) Madame Sosostris says, "And here is the one-eyed merchant, and this card,/Which is blank, is something he carries on his back,/Which I am forbidden to see." What he 'carries on his back' that she is 'forbidden to see' is his homosexuality (see item '2' above).
4) The one-eyed merchant is one of only a few characters explicitly mentioned by Madame Sosostris. Note that characters such as Marie, Stetson, the Thames daughters, etc., are _not_ mentioned, but Eugenides is. He has importance to the narrator on par with Phlebas and Belladonna. I believe this importance comes from the fact that he is the narrator's rapist.
5)A few lines in the facsimile edition, referring to the "ghastly hill of Cannon Street", make the Eugenides' assault much more explicit. These lines were not published in the final version, although the episode can still be inferred by a close reading with just the published lines. The facsimile edition has the lines:
(Philomela is raped)
Mr. Eugenides, the Smyrna merchant
. . .
Asked me . . .
To luncheon at the Cannon Street Hotel
Followed by a weekend at the Metropole.
. . .
(Typist is raped)
. . .
(Narrator envisions himself as Tiresias, observing the typist rape. This is a poetic device to allow the narrator as 'Tiresias' to recall his own rape, saying:
And I Tiresias have foresuffered all
Enacted on this same divan or bed . . . )
. . .
(Typist is observed after the rape)
She smoothes her hair with automatic hand,
And puts a record on the gramophone.
"This music crept by me upon the waters"
And along the Strand, and up the ghastly hill of Cannon Street,
Fading at last, behind my flying feet
Cannon Street is now 'ghastly' because something makes him recall his rape by Eugenides (perhaps some music heard along the Strand that was heard during the rape), as he runs away from the Cannon Street Hotel where the incident took place.
-- Tom --
P.S. For those who think The Waste Land is (at least partly) autobiographical, I quote these remarks from B.C. Southham, "A guide to the selected poems of T. S,. Eliot", sixth edition (p170):
The events described here actually happened. John Peale Bishop reported: 'Mr Eugenides actually turned up at Lloyds with his pocket full of currants and asked Eliot to spend a weekend with him for no nice reasons . . .'
Years later Eliot told an inquirer that while working in the City he had in fact received such an invitation from an unshaven man from Smyrna with currants in his pockets.