This "Lone Ranger" has only one "Tanto". When backing, I listen to only one and I've told "said helpers" that. I usually have the "said helpers" watch the front of the vehicle to make sure I'm not hitting anything up front. My co-pilot "Tanto" always has my back .... literally! No exceptions.
I had a couple occasions where the "said helper" was attempting to guid me. My "Tanto" was also guiding me. "Said helper" was leading me to disaster because my "Tanto" was guiding me with hand signals we both understood. I followed her directions. "Said helper" got fed up and left. We got into the site just fine.
So, it can and does happen.