Japanese Mispronunciations/Yazooka
Joe intentionally pronounces various Japanese words wrong to annoy the weebs in his audience. One of these words is "Yakuza", which he pronounces as "Yazooka" instead.[1]

This is a Joeism

When Joe says this, it's not a reference to any stream. It's just something he says sometimes.
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“Joseph Anderson Channel Two” video: “Danganronpa 2: Goodbye Despair - A Friendship Game (Stream One)” at 01:43:40.