Following his reckless desire for revenge, he'd made quite the spectacle of himself. No doubt Rodolphus was made aware that Antonin was searching for him, demanding satisfaction. The elder Lestrange was intelligent enough to put the pieces together. Even if he didn't think it was possible that Antonin could've uncovered the full scope of his treachery, it was enough. He would be causing waves soon. Now that the Dark Lord was dead, he could even come out of hiding. Maybe that was why Hermione felt so unsettled. She felt nervous that she would be used again to fulfill the wizard's nefarious plans. Mr. Akingbade might have assured her that he removed all of the memory charms, but even an expert made mistakes.