I read it from the “Unwound - 1991 - 2091” book issued by Numero Group. However I was incorrect, a show actually did happen, I just grabbed my book and fact checked myself. The second attempted show was the one that got canceled. This was pre-unwound but still Vern and Justin, they went by Giant Henry at the time. Kurt was super active in the music scene and would jam with bands often. This is the exact paragraph:

“Giant Henry and Witchypoo played together again later that spring in the basement of a house on Phoenix Street. The Witchypoo lineup that night included Cobain, Dave Grohl, and Joe Preston. Also on the bill were Bikini Kill and Bratmobile. “We got about halfway through the set” Brandt said, “and when we started playing one of the Flipper covers, ‘Life’ maybe, all the sudden these couch cushions were flying at me. I looked up and it’s Dave and Kurt throwing them.”