1. WPRT has contracts with many competative firms. Cummins for one. 2. It is likely the case that many of these contracts prevent the buyout from happening. In other words The Weichei contract is likely structured this way, or the Tata agreement or the Cat Agreement etc.
The liklihood of a buyout is small. This is a long term play and if you are looking for fast cash get on the rollercoaster. This stock movers +/- 40% in a matter of weeks.