Does Public Cloud support exposing internal vlan VM to internet via virtual gateway?

Hi all, I'm evaluating Public Cloud solution. 

I'm having a problem accessing to the public network via a shared private network and its vm-gate.

I created two almalinux instances and a private network (no dhcp, no gateway).

I associated a private IP address with one instance.

The other has both a private IP address and a public IP address.

VM_LAN: 10.1.3.168/16, gw 10.1.3.168

GATE: 10.1.3.168/16 + 152.228.XXX.XXX public

The two VMs respond correctly to pings between private networks.

In the GATE, I enabled connection sharing in the private network:

# sysctl -w net.ipv4.ip_forward=1

# firewall-cmd --add-masquerade --permanent

# firewall-cmd --query-masquerade --zone=internal --permanent

# firewall-cmd --zone=internal --change-interface=eth0 --permanent

# firewall-cmd --permanent --zone=internal --set-target=ACCEPT

# firewall-cmd --reload

From simulations on both another provider and local hypervisor, this configuration works without problems and I can reach Internet access from VM_LAN (e.g., tracepath 8.8.8.8 gives me the complete trace).

However, this doesn't happen via the OVH private network, see attached image. It seems like there's some blockage related to packet routing.

Have I forgotten something? 

Is there something I need to enable in the vrack? 

Does the OVH configuration prevent internet access from a VM on the private network via a VM-gate?

I've tried several times, including following  guides/community forums and on pfsense/opnsense (rebuilding GATE) too, but the problem persists.

It seems like a network blockage.

Ideas?

Thank you very much for your support.