My undesrtanding is that the Mayans only lived in an area Yucatan. The other people of Guatemala, Honduras, El Salvador, Belize and other parts of the Yucatan Peninsula are not Mayans. My source is ny brother who is a Mayan Anthropologist. He told that there are similarities in their culture but that they are not Mayans, they speak a different language altogether and that they enemies of the Mayans. He is trying to change this misconception that even some other anthropologist and archeologist have.
He currently teaches at the Unniversary of Arizona in Tempe, AZ. And every opportunity he has, he goes to Yucatan and lives with the Mayas. His name is Miguel Astor Aguilera. If you want you can google his name and read some of his works.
Thank you.