Jan and Cora Gordon with the Wallins in pre-WW1 Paris
Madame W- must surely be Elin Wallin (1884-1969) who lived in Paris with husband David from 1910-1913 at 43 Rue de l’Abbé Grégoire in Montparnasse-Luxembourg. I can picture her "carriage of an empress" and promotion of the married state (she and her husband became parents of seven children between 1906 and 1924). Her hair does not seem to be exactly white, however, and I can find no record of her skills as a masseuse.
Her husband David Wallin (1876-1957) was a celebrated painter rather than a sculptor, but his portraits and self portraits are entirely consistent with this account of tall collars. Use of the word "dude" is not obviously misplaced either. He won an Olympic gold medal for his painting "At the Seaside of Arild" at the 1932 Los Angeles Summer Olympics.
In using the word "sculptor", Jan Gordon is perhaps mixing up in his recollections David Wallin and his compatriot Gottfrid Larsson, who was a sculptor. In addition to the Larssons, the Wallins also developed a friendship with artist and photographer Erik Tryggelin (1879-1962) during those three pre-war years in Paris.
The identification of previously unsuspected connections between Jan and Cora Gordon and diverse artists from several countries in pre-WW1 Paris is hereby further expanded by the Wallin couple. They can be added to Marie Laurencin, Édouard de Max, Jean Cocteau, Francis Carco, Umberto Boccioni and all the other known participants at the Tuesday evening events at the Closerie des Lilas.