Here's another good video on this accident by a pilot I haven't seen on YouTube before. He has some good info though. Read his notes below the video. They show that the Lear was only 340' AGL at the threshold of 17 when the cancelled and went VFR. Downwind they were 400AGL, the last datapoint when they were turning base had them at 560AGL. The Jet was also just 0.8NM from the runway on downwind. Night Pattern altitude was 1388MSL, 1000AGL. He discusses a perceptual problem when coming in too low that leads to being too tight.
https://youtu.be/8-kVsCi41i0