Can I retrieve the actual crash detection info from my crash

From the above article:

"Sensor data from your devices are used to detect severe car crashes. All sensor data used to detect severe car crashes is processed on device and discarded after a crash is detected, unless you agree to share your data to improve Crash Detection."

Apple doesn't publish any details of what sensor data is stored, but I think it is very unlikely the crash sensors would monitor speed. If there was any sensor record it would probably be from GPS, but we have no indication this is actually archived by Apple Watch.