The interaction between throttle and elevator inputs (dropping forward speed and altitude at the same time) makes sense, and seems like a solid potential explanation. I may test that theory out sometime when I don't have anything around for it to hit if it doesn't stop quickly enough.
Now I just need to figure out if my sonar still works after taking some damage. I've mostly just been flying with VPS off to eliminate the possibility of damaged sensors giving inappropriate input, though nothing weird has happened the couple of times I've turned it back on. I can't tell whether or not it's getting a reading on the height above the ground when I'm in a low hover - usually when the VPS kicks in the bottom right number on my display in the DJI GO app changes from distance from controller to height above the ground (I'm using a Samsung Galaxy S5 so I'm not sure if something with a bigger screen would show both at the same time) but I haven't seen it show the height above the ground again since the crash.