I would not recommend myself watching the anime till they finish translating this part, there is some spoilers in the anime, as it seems that all of it is after the Adra part.
So the repairing is transform with Papillion magia other magus' crests and transplant them. Given what happened with Seigen, i wonder why the cat did not get out of the bag till now, as anyone close to the person that got the crest repaired would notice the changes in personality. Hell, if memories are transplanted, i wonde why no one went after Ashbourne because they could not withstand the memories from the killed magus asking for revenge.