Connecting to the British Columbia rail network would be pretty cheap compared to a new direct link to Alberta. They should Forget Alberta Oil and do it for the citizens of the state
“Forget Alberta Oil”
That is the bill payer for the whole project.
The problem with connecting to BC is the number of mountains in the way. The proposed route is in much flatter land north and east of the Alaska Range and the Rockies. Oil will be the main initial customer, but manifests will bring down the costs of consumer goods all along the route.