As much as I think two shooters would be plausible I cannot back that up with the actual evidence.
My 3D model is very consistent with the first bullet coming from Crooks position. I used James Copenhaver camera footage to fine-tune the model, because Google Earth elevation is not accurate enough.
Here are the link’s to my model: 1; 2; 3; 4; 5; 6
We also have Greg TDOA model on Mathlab. And here is his video demonstrating the model, with old data. Here is his latest findings with more accurate position of each source.
If there was a second professional shooter he would not miss. The ballistic simulations resulted in 4 inches drift from wind, which is can be compensated.