Slight vibration then engine shuts off

I was driving going about 40 mph when and all of a sudden I felt a slight vibration, not violent, just slightly coming from the engine I believe, when this happened the slower I went the more I felt the vibration, the faster I went the vibration was minimal. I was driving on local roads so when I slow down to make a turn at a green light the check engine light came on for only about five to ten seconds, then seconds later the engine completely shuts off, electrical was still on, gauges were not acting crazy at all, but I could not restart the car, it will not even crank at all. I attempted to give it a boost thinking it was the battery, but nothing, no crank, but electrical was still turning on and I no longer see the check engine light. I was told multiple things that could be causing this, the starter, crankshaft sensor, neutral safety switch etc. I have not done any work or attempted to diagnose the problem nor test anything. I am not sure if this matters but I had the transmission rebuilt two years ago, but had no problem with the transmission, even when I was driving and the vibration occurred I felt the transmission shift smoothly as I accelerated, no shifting kick back or anything. What could this be? Thank you