I think I've read something about this Gemini. But, like you I'm not sure who chased who. I do know it was Mike Lohmann who ended up in a bad way though. By all accounts he was lucky to pull through alive, let alone ride again.
The only other time i've seen someone blatantly knock somebody else of was also at Hyde Road. Steve Gresham kicked Louis Carr off as he was going round him. It was absolute madness! Must admit, we all enjoyed the aggro it caused though.