If WIU joined the OVC, it would definitely help them with travel costs. More than likely if they added WIU, they'd probably take Lipscomb or North Alabama and go back to divisions. The OVC also uses travel partners for all of their sports and their women's basketball is basically treated as JV (they play right before the men).
My guess is WIU wants to stay in the MVFC as long as they can since football is their most important sport. I have my doubts WIU will ever be D2. People act like they are going to close down, but as long as Chicago St stays open and stays D1 I don't see either happening.