Tulane did have four more wins than ECU, but Tulanes RIP is ranked 64th and ECU's is ranked 32nd. This is why ECU got into the tournament and Tulane didn't.
http://www.nola.com/tulane/index.ssf/2012/05/baseball_americas_aaron_fitt_q.html
http://www.nola.com/tulane/index.ssf/2012/05/baseball_americas_aaron_fitt_q.html