Good post supertoker.
On a DOT test there is usually a temp strip on the side of the cup. If its too hot just pour it into the cup and blow on it till the temp is about 98. If something screws up and the temp is too low. Rub your thumb briskly on your clothes and hold your thumb against the temp strip to get it back in range. Whe I was first doing subbing I would stick a digital thermometer in my sock so I could make sure where the temp was,high or low.
I have never taken a UA for a DOT test that the toilet water wasn't blue.