You can use CJDNS as a VPN, to access to the clear net. But the problem is that when it connects to IPV4, it has high percentage of being hijacked. Data get stolen. It is highly not recommend to have CJDNS connected to the clearnet. The best solution is to have megacorpISP provide IPV6 address for your CJDNS VPN.
This is where safe magic comes in play. CJDNS VPN connects to the megacorp ISP, then onto safenet. So you can have a CJDNS village that communicate to the cjdns vpn for safenet. It is theoretically possible to communicate between two networks. After all, cjdns changed the network level, upgraded IPV6 with encryption. That’s it. So there shouldn’t be compromises.