I've tested it. The website is very inaccurate as of now and I can confirm that. It says that pokemon like Iron Jugulis can be found in several different places with a 1% encounter rate, when in reality it can't be found anywhere else outside of area zero. Another example is sinistea. The site says that it can be found in every ruins biome, when in reality it can only be found near Zapapico and (if my memory serves) a small part of the bottom left corner of the map. Until the site is fixed, I think this question is fair.