If an MAO or other entity voids an accepted encounter containing rejected lines, and then submits a new, original encounter containing only the previously rejected (now corrected) lines, will the data submitted on the voided encounter be lost?

Yes. Data from a voided encounter will be considered inactive. If an original, accepted encounter containing rejected lines is voided, the submitter should submit a new original encounter to include both previously accepted lines and corrected data for rejected lines.