I might try this later with a rifle in my hands. I had heard of Roe investigating noises in the rut but had never experienced this with fallow.
Interesting story, thanks.
I was out looking for prickets in a large wood with a coppiced hazel understorey, and was drawn to the sound of two bucks locking antlers. I moved upwind to within 30 feet but the bucks paid no attention to me whatever, they just kept on fighting. It is often the case that pricket will watch a fight too and, behold, on the other side of the bucks, stood a pricket. We both watched the two fighting bucks for a couple of minutes then I shot the pricket. The bucks broke off and moved off 50 feet before resuming their fight. In full view of the two bucks I openly walked up to the dead pricket and started a full gralloch, while the bucks continued. They eventually moved off after I threw stones at them.
The lesson here is to investigate the noise of fighting fallow as there is frequently a pricket in attendance also.