It is essential as you won't have much time right after you land at the Stadium only because either the keycards despawn after 4-5 minutes reportedly or someone else will get the keycard.

Do the Stadium keycards spawn every game?

Each key will appear somewhere on the level it's for, so if you're going for all three and the final Stadium access code then you really need a team to split up and take it all on at once. Remember, these keys only exists for about the first five minutes of the game, or until the first ring starts to close.

What's the 8 digit code in Stadium?

To gain the eight-digit access code to the stadium in COD: Warzone players need to find all three keycards for doors EL21(Top, Executive Level), P216(Parking level), and CL19(Middle, concourse level). These keycards can be extremely tricky to find as they spawn across the stadium in the form of random loot.