I have a friend that does work for alot of sports events and when asked the question about who could host such an event and how Missouri did..this is what she said:

Missouri held theirs at Mizzou Arena in Columbia which holds just over 15,000. There are four school size classes in MO for wrestling. During most of the finals, 70 to 75% of the seats were full...which I think is a pretty good turnout. ... As far as venues are concerned, I think the following could hold 8 mats: Intrust Bank Arena in Wichita (15,000 seats), Koch Arena in Wichita (10,500), Kansas Expocentre in Topeka (10,000 seats), Bicentennial Center in Salina (7,500 seats). Allen Fieldhouse holds 16,300 and Bramlage Coliseum can seat 12,500, but I'm not sure they can retract the bleachers back enough in either of those venues to accommodate 8 mats. If they're really considering moving back to having all the classes at one venue, they should really contact the Missouri State High School Activity Association (MSHSAA.org) to see how they run it. It was a well-oiled machine. I'm also think Iowa runs an all-class tourney as well.

This is information relayed to me...