However, since it is on admissions.vanderbilt.edu , it is unlikely that it would have been shown if it were a highly segregated sorority, for school marketing reasons that should be obvious.
Sigma Phi Lambda at Vanderbilt is also unusual in that it is an explicitly religious sorority. It may be doubly unusual in going against the common segregation in both the sorority and church domains.
Someone concerned about the possibility of sororities/fraternities being heavily segregated should look at more than just one or a few chapters. (Note that high levels of segregation in sororities/fraternities are not limited to colleges in the south.)