I think what the OP is trying to point out is that this would be seen as an "oh shit we don't know what went wrong" consulting job rather than a "we knew we weren't good at this from the start, so we contracted out to another company who was" job. They've already implicitly asserted that they knew what they were doing by putting the batteries into a certified plane, so this would likely be construed as an emergency cry for help.

Also, most of the time the use of consultants isn't publicized - taking help from Elon Musk would no doubt be broadcast heavily by the media, and most likely not in a positive light.