"What LiDAR does show"
FP says : "As I write I'm looking at a LiDAR survey ...... It shows the ground contour as one would expect, but it does not show objects upon the ground. This is most likely a higher-level survey than you're considering but, particularly if the craft is buried, I think the best you could expect would be (as you say) to locate the 'dozer workings and hope that leads you to the area you'd like to inspect in detail......."
I have some LiDAR pictures in greyscale of a mine site in the northern hemisphere and it shows the vehicle tracks, earthworks and minesite buildings and dams very clearly. We would be interested in the bulldozer tracks and as you say they hopefully would lead to an area or areas where intensive earth moving has occurred. That was all we could wish for.
We know that the BD driver made cuttings along the track where there were lumpy irregularities and we know he filled in some depressions all in order to smooth the way a little for the jinker when carrying logs, so the cuttings will show up as would piles of moved earth.