I find it interesting you think MSG was the problem here. By all accounts this should be a really great MSG dish. Are you sure it wasn’t the apple cider vinegar? It seems oddly sweet while also maybe interacting poorly with the mayo
Was the texture noticeably different to just using a hand blender on low and mixing ingredient+yolk? I’ve never had an issue with lumpy deviled eggs which is what I assume the sieve was intended to do