As I described previously, DNS64 resolver will replace DNS A records with DNS AAAA records that are IPv4 addresses wrapped in 64:ff9b::/96 IPv6 prefix. This IPv6 prefix is routed to our NAT64 box that will perform NAT between IPv6 and reach IPv4 only networks using shared IPv4.
Your IPv6-only VM <- IPv6 -> Our NAT64 box <- IPv4 -> Github (for example)