There is now another option at Epics mercy, https://code-orchestra.com
Plenty of videos and blog articles on it. Epic continues to say no to fair, equitable, and sustainable terms for C++ extensions (their right since it’s their engine) to the detriment of the community.
A few simple clear agreements (SLA’s, transfer rights, etc…) would easily address Epic’s concerns; it would expose UE to millions of devs and potentially open up a large talent pool for UE-based studios. A fair and equitable solution is easy to reach if Epic Games is open to it.