Sims 4 EVENT BROKEN

how can i reset the event? im stuck at building this stupid time travel thingy.. but i had to delete my old folder because i had to create two sims because the infants just refuse to eat and this overly buggy game is just sometimes too much for my nerve, and because of that i had to create a new sim.. but noone told me that you can do this event ONLY WITH ONE FAMILY.. 

so that means my progress is all gone.. because all those sims with the knowledge of the event.. gone.. deleted.. nomoreand now i cant build the time travel machine because my new sim has NEATHER those time splinter things, nor did they read about the thing that is necessary idk

how can i reset the event? and no, i do NOT USE ANY SINGLE MOD, my game is vanilla