I don't know if this counts but because you said successfully or not I'll include it: Duwatna was on Street Hoops teams for several of the Gosu weeklies directly after release. I think bl4nk was also on that roster, but he later made it onto an iteration of Gale Force (http://wiki.teamliquid.net/overwatch/Gale_Force_eSports) so he is more likely to count. Flame played on Splyce for a short time, too.

Isn't this supposed to start today? Their website hasn't updated the schedule from the open qualifiers.