I doubt that the highlights are anywhere near actually blown, it's just that the highlights are much brighter in relative terms than other parts of the image (i.e., large subject brightness range), which may be much darker (again, in relative terms), so it's difficult to display all of that information. If you were scanning this yourself, you could make a local adjustment (as the detail should still be in the negative) on either the darker or lighter parts of the image with a virtual ND grad, for instance.
Labs, however, only make global adjustments to images, so there's no way to balance the exposure between bright and dark unless you do it at the time of exposure with an ND grad, I've found (Edit: if scanned to jpeg anyway).