Most times you pull that slide the back takes the A gap because the guy blitzing there is a more reliable pickup than a lineman. Bradbury pulling an audible there to the left only means the guy he picks up comes through at basically the same time. It was blocked correctly. It wasn't reacted to correctly by the QB.
Darnold has to see the overload blitz and throw instantly. It's an easy first down if he does. That one is 100% on the QB not recognizing the blitz and 0% on the blockers. (The only caveat is if Bradbury misidentified the mike. But I don't think he did, Darnold could've taken that snap, fired to Addison)
As the game wore on they changed their protections to have more options for overload blitzes, but the team better be ready to see more of them now that the Cards are on tape getting easy sacks because the coach/QB refuses to throw hot. (Edit: It's possible Addison didn't get his head around fast enough too)