Those rumblings were from last season. The Mavericks owners did change the name of the team to the Kansas City Mavericks but is committed to their home in nearby Independence. The Chicago Wolves primary affiliate this year was Vegas while St Louis (previously with Chicago) still supplied players to the Wolves. St Louis signed a five year deal with the San Antonio Rampage (owned by the Spurs) beginning in 2018-19 with no intention for relocating to Kansas City.
The ECHL I can see in a few years going back to its old footprint of east coast and midwest teams. The league has been recently moving into former AHL markets in the east (Adirondack, Maine, Manchester, Norfolk, St. John's and Worcester).