If you uninstall the VZ access manager, does the card still show up as a modem in Device Manager?
Because you might try just uninstalling the VZ access manager, create a dialup connection for it in Internet Options on the Connections tab (easier than using the wizard from Network Connections or Network and Sharing, IMHO), no username or password, speed 921600, and dialing #777 (all CDMA/EV-DO systems I've seen dial #777 to make a data connection).
If you uninstall the access manager and the card turns up as 'unknown' in Device Manager, it might not have the proper drivers to begin with.