I have no way to know if your settings are right or wrong.
There are many cases where you will see Telus indicators (e.g., the initial boot-up "splash screen"), but they should mean nothing. But, anyplace where you can change a setting AWAY from Telus would be of course a logical thing to do.
I highly doubt that you will ever get Internet services to work via the native BB Browser. That requires a functioning BB-level data plan...and from all you've said, Petro is not a BB-supporting carrier. So none of the BB-proprietary services are ever going to work, and that includes the native BB Browser.
Occam's Razor nearly always applies when troubleshooting technology issues!
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