Hosting a server on a VM, can't connect

So my friend is hosting a rust server on a virtual machine (win 10), and it won't connect.

in the VM, he edited the NAT type's IP to 192.168.19.129

he ported 28015 and 28016 through his firewall

so my question is, like.. let's say his regular IP is 74.55.55.55 for his home, and he changed the VMs ip (NAT i guess?) to like.. 55.66.66.66, would i do F1 > Connect 55.66.66.66:28015 (The VMs IP) or would you used his Homes IP 74.55.55.55:28015 even though it's hosted on a vm and the ip changed through nat or whatever
also, i tried his vm's ipv4 (vms ip that was changed, you know)
and his Ipv4 DHCP server's ip of the vm (screenshot is here)
When connecting to the IPV4 DHCP server of the vm's changed ip, (I entered this in the console.. connect 192.168.19.254:28015) it showed this, but then doesn't connect all the way. Screenshot here

hope i can get some help, thanks!
[DOUBLEPOST=1487625366][/DOUBLEPOST]I turn off my windows firewall when doing it, also. just in case it were to have any interference.

 

You cant connect with his internal ip you need to use his external and he needs to set up the external ip in his bat file and thats if it is a virtual from a hosting company not something he set up from his home

 

Setup the external ip in the starting bat? How'd you do that? I always thought you can only bind to your local ip when running the server in a vm behind NAT.

 

IDK, but can someone give me example code for the bat file or something? i need some help. much appreciated.