Well I can already tell you that whoever stole the package is going to have a hard time trying to use the modem since it needs to be activated for it to work... Best of luck hopefully you don't end up having to pay for the modem
Call customer service and escalate it up if the rep is telling you they can't call Canada Post to confirm its been lost. I'd imagine front line reps can't really call Canada Post on their own to confirm the package has been lost and it's up to manag...