I've also never heard of a specific olympic deadlift, but it makes sense that there would be a difference between deads as a complete lift with the goal of max weight and deads as an assistance movement for clean or snatch.
As for the squat, again, the differences are a function of the different goals. Oly lifters train front and back squat as assistance to the oly lifts. When performing the second part of the oly lifts, the spine is very upright. This is because the weight is either over the head for the snatch or racked above the chest like a front squat during a clean. The hips travel more up and down, instead of back then down like a traditional powerlifting squat. This increases the importance of leg flexibility because the lower you can get the less height you need to get the weight racked, and leg strength because once you get the bar racked you actually have to get standing again.
The need to get really low with an upright torso is what determines the form of the oly squat, which means high bar with closer feet. This focus on quad development and full range of motion is also why bodybuilders tend to prefer this technique.