getPageBox returns different results from Preflight

I have a document where some pages appear to have an origin other than the corner of the page. PreFlight shows this in the value for both CropBox and MediaBox

But the getPageBox for Crop and Media returns 0,0 as the origin. Consequently, any attempt to add a form field or link gets positioned incorrectly.

I could make adjustments manually if there were some way to tell this is happening. Is this a bug in getPageBox? Is there a way to obtain the PreFlight values from JavaScript or IAC?

Here's an example page: http://plummer.us/BadPage.pdf