Roster substitution name

I am designing a multi-selection roster set of questions, referring to a predefined list of species selected by the user.

The roster displays correctly questions according to the number of species selected.
However it does not indicate by default the species corresponding to a given set of questions (see enclosed screenshot). Instead, for each new species, it just repeat the name of the roster, without providing the name of the species.
When using text substitution with reference to the list of species, I got the error message “[WB0018]:Substitution references an item that is not supported in substitutions.”

How can I get this names?

Thanks!

See the Burgers section in Public example User questions and common patterns questionnaire.