Going by the typical marketing practices of Idol groups, they would definitely go with 4 versions: one for each team and the theater would have a Kenkyuusei song. Maximizing the money milked from fans.

Considering shonichi was put on Namida Surprise! after B's 1st original stage and SKE's Banzai Venus had a song for KII, I'm thinking the chances of a Team 4 song being on an upcoming single are pretty good.
News for today:
Team 4 has gotten their 1st Stage! It will be a revival of H1: Boku no Taiyou and starts in October.
and
Preview for Kaze wa Fuiteru is out: