Edit: looking up a bit more, it seems like this idiom is used to denote goods sold for cheap because they were stolen. Like "Bob is selling genuine iPhones very cheap, I fear they fell from the back of a truck".

Edit edit: I initially took it as "we won't tell how we got this", because I didn't know this idiom, but it seems several people agree with this interpretation. Not necessarily stolen, but obtained from an undisclosed source.

One of the screenshots[0] shows the VMware Tools Service running, so yeah, looks like a virtualized guest.

[0]: https://signal.org/blog/images/cellebrite-dlls-loaded.png