the comparation is a little silly
nobody expects anything amiga related, even if open source, to become a success like Linux
I already wrote that it is dangerous for software on a small market to be dependent on the decisions or fate of one person. If Cloanto wins and they cannot come to a agreement with Hyperion (Ben H.) 3.1.4 is dead and all your work vanishes. If 3.1 would have been open source and you would have contributed to it, it would not be important what anyone else does. And as I already wrote too... the danger of lots of forkes is not big because you need skilled devs for it who want to do it. Those are rare in the amiga community so finally there would very propably be just one fork you (perhaps together with one or two others) would manage. No different than now, just without the danger of being killed by others. And it would be easier for people to take part because of no NDA to sign. I cannot understand your aversion against open source. Even if it is a little more chaotic the advantage of being independent outweighs the potential disadvantages, at least for me. And the problems closed source has is obvious when you look at the situation of Amiga OS. The same already happened to lots of amiga software.
It is anyway just a theoretical discussion... it all depends how the legal argument is decided. Nobody here can influence that and nobody will ask you either. If Cloanto really open source 3.1 (what they repeated a couple of times in recent years) you have to think if you want to continue. In this case 3.1.4 is in doubt anyway because of the 4.1 sources you used (as I understand it). If Hyperion wins or it ends without decision nothing changes for you.