The roaming rates were not in the contract or anything else she was shown or told at the verizon store when she bought the device. And, she bought it specifically for use in Canada when she's visiting her family, so she did ask if it would work there.

I eventually found the rates buried on the verizon website several clicks deep through greyed out deemphasized links in the mifi data plan options. They're not available anywhere in her account information. They're also displayed in a hard-to-read run-on sentence style that mixes all countries together, not an easy to understand table. Verizon is clearly trying to hide this information in order to trick users into huge charges.