Portuguese to English Other Journalism industry magazine article

"Fui atrás do curso de preparação de voluntários do Grupo Cuestalhaços motivado por uma colega de trabalho que estava com problemas de saúde."

"Atuo como cuestalhaço aos finais de semana."

This is a play on words, and I won't translate the proper name of the group; however, I'd like to understand its meaning. I know "palhaço" (clown) is part of the construction of the word, but unclear about what "cuest-" means. Thanks very much for your insights.