Excellent question and thanks for the very helpful example. The entry words are English, and they are brailled in English with contractions. These entry words will also be the guide words on line 25, again fully contracted.
The Spanish will be Spanish with the special accented letters and so on according to the Interim Manual. The print sets off the Spanish entry word with brackets. Follow print and use braille brackets as well. This arrangement is enough of a pattern for the reader to get the idea. The reader will also have seen the glossary in English and so will easily recognize that this next glossary is Spanish. And the reader will no doubt have noticed by now, as we all have, that these translated glossaries in non-foreign language textbooks are now quite common.
Don't forget to list the Spanish accented letters and any Spanish puncutation that may occur as special symbols.