Are you aware of other comparable 19th-century composits from Paris, or from other companies? Am I right in assuming that each of these dancers would also have her "own" card in the collection?
i know of a related composite card from Paris reproduced in the catalogue for DEGAS AND THE DANCE which is a 'collage' of just the dancers' lower legs and feet.
the person who previously owned this cdv states as follows:
"This CDV by Disderi (with his mark in miniscule on the obverse [lower right corner] but no stamp on the reverse) records the photographs AND NAMES of 37 ballerinas who performed at the Paris Opera in the Romantic Era and on into the period of the so-called Second Empire. It is an important document because of the names accompanying each of the photographs, making it an ideal tool for identifying cartes-de-visite of the various ballerinas of the period. The names are written in small letters, readable with a magnifying glass, at the edge of each photographic oval."
i know too of a Russian series in which the letters spelling out NASH BALYET (Our Ballet) in cyrillic, are filled out by various post-card-styled photos of imperial Russian dancers from a bit later in the 19th c.
so yes, both the French and Russian composites show images that exist in their photographer's studios as single portraits, which get recombined into various "collages" so they can be re-photographed to produce these group effects.
but, no, these are all danseuses of the Opera, there are no images of English royals among them.