Well things like the Twister are neck cranks. A lot of tournaments don't allow neck cranks because they are kind of dangerous.
I might be a little rusty on my 10th planet but I don't see a whole lot of small joint stuff goin on.
Can you get a list of what technique was used when the fight ended in a DQ? Might help point out why it was a DQ. You would also have to get the rules for each Tourney, they vary from place to place.
Like the tourney's where I am dont allow: Neck cranks, Heel hooks, twisting leg locks at all, and only black belts are allowed to do: Calf/Bicep cutters, straight ankle locks and kneebars.
Isshinryu Karate 2nd degree Black belt.
Neko-Ryu Goshin Jitsu 2nd degree Black belt.
Jujitsu 2nd degree Black Belt.
Isshin-Jujitsu 2nd degree Black belt.