Antonyms for the word "more documented" could include "less documented," "unverified," "unsupported," or "unproven." These antonyms indicate a lack of evidence or substantiation, in contrast to the quality of being well-documented. Other potential antonyms could include "scant," "sparse," or "limited," all of which imply a shortage or deficiency of information. In some contexts, the opposite of "more documented" might be "hearsay," "rumor," or "anecdotal," which all suggest a lack of reliability or credibility. Ultimately, the choice of antonyms depends on the specific context and the intended meaning.