check the folder inside qdl/qfill_app/modalai/voxl2-mini_SDK......
Make sure that the ufc folder is present inside (occasionally after downloading the Flat Build and unzipping there might be voxl2-mini_SDL/voxl-2_mini_SDK). Make sure the path is qdl/qfill_app/modalai/voxl2-mini_SDK....../ufs
Edit: Also, you have the wrong download for the flat build. You are currently using the SDK instead of the flat build file. We will send you the correct link to the folder in a few minutes