I know its his router because i had same issue till i configured my router whcih i have Linksys!
But the ports should look like this when forwared im not giving you my whole Linksys screen just the forwarded categorys!
He just needs to configure these ports like i did mine!
NOTE- is ip may look different thats ok!
If he cant figure it out im sure Chief,Stevie,BB Mike,or Panther knows something about the other routers!
But as you can see the last digit of my ip box are empty i erased them for example you must plug in the empty boxes for your ip address part that doesent show up for example it kept all bt the last number i had to put into there myself!
Say your ip was 168.234.1.2 then you would put 2 in the last box!
If your unsure of your ip then on most computers not sure if on all the command to renew and release your ip which also shows your ip is winipcfg!