Hi!
The command should be failling because you are missing -L, look what I wrote avobe, iptables -t nat -L, so if you are not getting repsonses it should be because some packets are stucked, try to flush iptables first:
iptables –flush
iptables –table nat –flush
iptables –delete-chain
iptables –table nat –delete-chain
iptables -P FORWARD ACCEPT

Enable port forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward

Then run the proper iptables rules again and try it once more.

Let me know how it goes!
Diego