GrapheneOS devs should approach the EU for support here in my opinion.
Right about now the EU, or at least many member nations, are very interested in ensuring ability to take ownership of important/critical solutions.
"Experts "deeply concerned" by the EU plan to weaken encryption" https://www.techradar.com/computing/cyber-security/experts-d...
As for whether or not the EU can or will help them, I have no idea.
The legal changes require to force then to do so are wildly beyond what we can expect from the EU.