for instance, I had one group take the speed they estimated from the video, and the speed they estimated from the energy calculation, and average them together, basically as a compromise between two people within the group
If you only care about betting odds, then feel free to average together mutually incompatible distributions reflecting mutually exclusive world-models. If you care about planning then you actually have to decide which model is right or else plan carefully for either outcome.
… Which is a whole different lesson: