I have no problems with my Sorors or my Frat having parties with whomever they want. We have no regulations banning such activity. Swamp Thang,why assume the worse?
Now some of you may not know it...but Zeta Phi Beta Sorority was introduced to the campus of Howard University by the ladies of both Alpha Kappa Alpha and Delta Sigma Theta in addition to my fraternity brothers. Thats factual history. Why would that be considered odd? They( dst and akawere there first, and thats just the way you do things...etiquette in presenting was actually very important at one time.
The akas and deltas here in NY had a party last summer...it was called "OOOWeee"

(Cute concept) From what my Kappa friend told me interaction between the 2 was BAD. So maybe they will try again next year. Again, if we want to look at the historical significance, was it really a bad idea? The 2 organizations share a bond in Sisterhood from the beginning...why should aka and dst not embrace it today?
On the fraternity note...
The Black Man better get his house in order and stop sweating the BGLO affiliations...
Y'all still very much an endangered group. Anything you can do to behave in a more unified manner consistent with cultural enlightenment, service, achievement, friendship, not resting on tradition through fellowship is only going to be positive in the movement.