If you have a pebble-covered drive in place at the moment, you could do your own mini-survey and very carefully dig down a bit to see what is under there. VM cables are usually installed in the cheapest/quickest way possible. Often that is just buried direct just an inch or two below the surface.
If you do already have conduit under the drive, there is nothing to stop your driveway installer burying that in the sub-base of the drive as long as each end is accessible. If you don't have any conduit in place your installer could fit some for you as part of the driveway build and you could put the existing cable though it. There is usually a connector plug in the omnibox on the wall outside which would allow you to separate the external cable from the internal cable so you can thread the external cable into some conduit.
If you are putting in new conduit you could also leave in a nylon draw rope so, if you ever needed to pull another cable through in the future, once the driveway is laid you would be able to do that easily as long as each end is accessible.
VM's cable-installation process are a source of regular complaint on here (due to delays in installation and general chaos around the process). You may be courting disaster by getting VM to relay your cable, if there is nothing wrong with it.