Legitimate TELUS employees or a scam?

A group of apparent TELUS employees on Reddit are offering to sign people up for TELUS services using their own channels and with their own referral program. They use a genuine telus.com email address ([email protected]) and use the phone number (855)-645-3159. I'm tempted to sign up through them, but am cautious of scams. Can anyone at TELUS confirm whether this is a legitimate TELUS number?

Thank you