> could there be an error in the marriage record transcription?
The only way you will find out more information is to obtain a microfilm of the county in question and look for yourself to see if you can find any more clues. Who knows? The age of the Meredith who married in Lowndes County might be all wrong. Or it might be spot on.
Indexes and abstracts almost never provide all the information one really needs. Originals are preferable.