Hello Cruisingsince1982, I just got off the Encore Sunday and even though the documentation says as shof515 quoted, the folks at the Cruisenext desk told me you could use your one "lower tier" restaurant certificates at Onda.
I ate at Los Lobos, based on several recommendations (as well as the recommendation of the Cruisenext folks) and it was excellent. I highly recommend the fresh tableside prepared guacamole and the tex-mex style snapper. Both were fantastic.