There are several synonyms for the phrase "vouched for" that can be used in different contexts. Some of these synonyms include "attested," meaning to confirm or verify the truth or accuracy of a statement or fact, "endorsed," indicating approval or support of a person or idea, and "guaranteed," providing assurance or certainty of a specific outcome or result. Other synonyms for "vouched for" include "certified," implying that something has been verified or confirmed as true or accurate by an authoritative source, and "validated," meaning to establish or confirm the validity or authenticity of something. Depending on the context, all of these synonyms can be effectively used as substitutes for "vouched for".