If you had a popular website, then you might see this traffic for weeks or months. I work for a company with a top-100 global website, and when we change an IP address or change a cache breaker we continually see traffic coming in for a very, very long time.
There are all sorts of badly behaved tools out there. Badly written scrapers by university students, badly written scrapers by professional search engines, badly written botnets.
There are also badly behaved recursive DNS resolvers, although these are becoming less common, and caching for > 14 days would be very, very unusual.
It's plausible that these 200 hits you're seeing are not even real people - especially if they're just sending the
It is also possible that these are users who are hitting your old ELB URL directly for whatever reason - you've mentioned that the ELB is for some reason indexed by Google. You could always use the Google advanced search to see if it has any reference to 3rd party sites linking to that URL.