You are right, I have stopped trying to understand your logic, since every single time these days, you end up with positions that contradict yourself, whether it's on the length of a round (with the silliness of having characters freeze in time for 6 seconds multiplied by the number of other combattants) to now the action of throwing a dagger being both what starts combat and something that happens during combat itself. You end up in impossible positions every single time because you create rules that are purely your own based on your personal view of realism. Once more, the RAW do nothing of the kind and other DMs don't have the same views.
Look, it's not difficult, the RAW says three things:
- A: Roll initiative. Everyone involved in the combat encounter rolls initiative
- B: When combat starts, every participant makes a Dexterity check to determine their place in the initiative order.
- C: The DM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure. When the outcome is uncertain, the dice determine the results.