You will need to provide at least some specific details on the problem for anyone to be able to offer any suggestions. So far I've never had to set up custom port forwarding for any game I play.
What in-game services?
Which platform? (PC, Xbone, PS4, other)
What is the exact error message?
What is the exact brand / model of gateway/router/wifi device you are trying to configure? There isn't a device I know of named "Telus Wifi Hub". If you can't find the model, post a photo of it. If you're on fibre, you should have been given the T3200M gateway that looks like:
Interesting. I've never seen that device before... I didn't have to port forward GTA on my T3200M and it worked. Not sure exactly what difference in wireless or routing functionality there is between the T3200M and the device you have...
@dru can you shed some light on the new hardware since I cannot locate any details on Telus' website? Is it a replacement for the Actiontec?
The wifi hardware won't have blocked ports. The external network will but only very few specific ones and those should not affect gaming in general. If a VPN is allowing it to work, then it's likely not a port forwarding issue.
The short list of blocked ports for incoming connections (ie if you're trying to run a server):
TCP 21 (ftp)
TCP 25 (smtp)
TCP 80 (www)
TCP 110 (pop3)
TCP 6667 (ircd)
TCP/UDP 135-139 (dcom and netbios)
TCP/UDP 443 (ssl)
TCP/UDP 445 (ms-ds)
TCP/UDP 1433-1434 (ms-sql)
GTA:V on PC typically uses ports: (UDP) 6672,61455-61458 which won't be blocked.
For outgoing connections most likely and those will work fine. Port 80 is commonly used for web browsers. 443 is for secure connections. Those ports won't be an issue unless you're trying to run a server of some kind.