It is absolutely true that we do not definitively know his plan here. All we know is his history, and his statements.
The history is a pretty strong indicator, however. M&A is his go-to approach. "Among Sarissa’s successful investments were Idenix, which was sold to Merck for $3.85 billion, ARIAD Pharmaceuticals, which was acquired by Takeda Pharmaceutical Co for $62 billion, and Bioverativ, which was spun off from Biogen and then sold to Sanofi SA for $11.6 billion." And there are others.
When you combine that history with the blunt fact that GIA is the Road to Hell for this one-drug company with no real game plan, it's not a big stretch to think the plan is to sell this turd.