Water and finished dough temperatures can be quite tricky, especially when using a new mixer for the first few times. The 100 degree F temperature you mentioned is the temperature normally recommended for rehydrating active dry yeast (ADY), although some instructions on yeast packets of instant dry yeast (IDY) often recommend temperatures above 100 degrees F when the IDY is combined with dry ingredients. Those higher water temperatures are usually intended for home bakers to essentially guarantee that the doughs will rise, which is the most common problem experienced by home bakers. The instructions for professionals are different, since they presumably are smarter than home bakers in the minds of yeast producers and can work better with lower temperatures. If you look at the packages of IDY sold to professionals you will ordinarily not see water temperature recommendations.
The finished dough temperature in any given case will depend essentially on the ambient room temperature, the flour temperature, the water temperature, and the frictional heat component contributed by the mixer itself, which is sometimes referred to as the friction factor. The friction factor is determined primarily by the type and model of mixer used, the shape of the mixer bowl and the particular attachment(s) used, the dough batch type and size and its hydration, and the speed(s) and durations of the mixing/kneading. Autolyse and similar rest periods will also affect the finished dough temperature, as may the introduction of starters and preferments (depending on the amount and temperature). Changing the dough batch type and size will result in a different friction factor, even if everything else remains the same.
Many operators arrive at the right water temperature for achieving the desired finished dough temperature for the particular batch type and size used by selecting a water temperature and adjusting it in five degree increments in future batches until the desired results are achieved. You might try using water right out of the tap as a starting point and go from there.