So I'm following the directions (pasted below for convenience) in https://www.telus.com/en/bc/support/article/set-up-telus-home-assistant-on-your-google-home-device to connect Optik to my Google Home, but I can't seem to get it to work. I get to step 8, and when I hit the big green Allow button, it simply kicks me back to step 4. After that, it doesn't ask me to log into My Telus anymore, it just immediately goes back to step 4 when I select the TELUS Home Assistant in step 5 - because it already recognizes that it is linked. However, it never shows me any of the devices connected to my Optik account. I've removed the link to TELUS Home Assistant from my Google account and started over several times, but it seems to do the same thing every time. I never reach step 9.
Sorry to say you are not the only one, I had started posting over at https://forum.telus.com/t5/Internet-Home-Phone/Telus-Assistant-fails-to-register-on-Google-Home/m-p/... with the same problem as someone there once had the problem and had it corrected. But it appears to have gone sideways again.