Enough Nazi leadership was “on board” that the machine of death was probably going to continue to churn even without Adolph. Certainly he was trying to establish a “thousand year rule”, there would inevitably be other successors.
That said, sure if the opportunity was there they should’ve taken Hitler out.
That is the thing about tyrants, they always think that their effort will last forever.
Just like the @$$hole in the White House right now - he forgets that he too is subject to Lady Fortune.
Just when they think they have it all - it will all be reversed.