My 2-cents:
1. Own POET fab would mean to compete with their own customers. Not a good idea!
2. There is no need to own a fab - this is yesterdays thinking. Today is Fab 2.0, and all these products "Powered by POET" will be "their" products!
But I see plenty of options and possibilities to grow for PTK. Noone knows this technology better, they are now the specialists. A genious like our Dr. GT will attract the brightest brains for their R&D department. So they can seed new fields of applications now. They can stake these new territories before others will even think about them.
So I see the future of POET as a big think tank, the IP company for opto-electronic and quantum semiconductors of the future. A little similar to ARM, but with a more basic but superzize field of research.