It does not seem unreasonable to me that STAM would try to extract as much value as they can out of their investment, with the initial bet having gone awry.
Does anyone here know about the story of CMI limited (ASX:CMI)? I only followed the story loosely back then but from memory didn't they go through something where a substantial fundie shareholder tried to wind up the company because it was trading at below net asset value? Looking back at the announcements now, I see in April 2011 an EGM was called to vote to wind up the company. The vote was held in June and failed to pass. It looks like the fundie went on to sue the directors for breach of duty, which was eventually resolved when the directors agreed to do a share buy back in exchange for the litigation being dropped.
I wish I followed the story more now, so I could have a better grasp on how an activist shareholder scenario might play out. It does look like there could be parallels here with OMN though. A big difference would probably be that CMI had cash generating assets, while OMN would be a pure cash play. But I wonder if there are lessons there.