has anyone had this happened to them i was trying to do a prologue speedrun using the stock car glitch and when i do that when the shootout comes there's cops everywhere a helicopter spawns and brad and michael shooting at each other and trevor i was playing on a series x so i wasn't using mods here's a clip i have of it https://streamable.com/ewtmuo

Stock cars breaks some mission logic when it quits so you get a lot of weird behavior, best thing for stock car on Prologue is to let the race fail then shoot Brad to go to vault cutscene checkpoint, mission goes back to normal after a fail like that.