Looks like that's a rocket launch from Vandenberg Air Force Base. Note the video is super fast time lapse and all the little lights are planes taking off for LAX.
https://twitter.com/LionelMedia/status/1290291014389776386
“sky event?”
Looks like the whole video was sped up. Look at the speed of the cars at the bottom. Would make the sky objects look much faster than what they were probably going.
The “bloom” is very unusual, though.