A common issue with MX when using IKEv2 is that only a single (source,destintion) subnet combination can be active at a time. So if you have 3 subnets in the first org and 4 in the second, of the 12 combinations only 1 can work at a time. IKEv1 doesn't have this issue on MX. Consider using IKEv1 if you are not already.
If one of the orgs has a lot of sites, a more scalable solution is to get an additional MX and run it in VPN concentrator mode. Add it to org1, and install it behind a hub MX in org2.
In org2, and static routes pointing to the org1 MX behind it, and distribute those into AuvoVPN.
In org1, and "local routes" to the VPN concentrator sitting inside of org2.
Then all spoes (and hubs) can talk to all other spokes (and hubs).