It looks like you didn't even bother reading the link you posted. The paragraph discussing building the stadium for your fighting Illini in 1921 as the first known usage for athletics is a good spot to look.
This is common knowledge for alumnus and fans.
The new mascot should be easy and in today's environment, popular with a lot of people if tastefully done. A WWI costume slightly characatured for the big stage and pay homage to the troops and modernized version of a patriotic WWI song. They should just do it and get it over with.