Easy way through for Hyperion if it wants to keep 3.1.4 on the market is to sell 3.1.4 as a collection of diff patches with a patch script and call it the Hyperion software enhancement or AmigaOS 4 Classic Patch, or something they actually have rights to.

As long as they don't mention AmigaOS, Amiga, or distribute binaries of AmigaOS components, 3.1.4 would no longer be legally contentious.

Probably unsaleable as well, but you can't have everything. Although Hyperion certainly do try.