Vlade didn't get rid of Mike Malone. PDA did. When Vlade came to power PDA's ,"Luke Walton", George Karl was coaching the team. And instead of just canning the ousted GM's preference choice who was starting to sour the locker room he stuck it out for awhile. During that time things became so sour with the teams franchise player that not only did Karl go, but so did that player, so... good lesson to learn. Very timely too, did Vivek learn that one or does he want to go for round two this time with Buddy Hield and potentially De'Aaron Fox as well?
As for Doc, he's another one of those rarities for Vivek. While every coach is fallible he's a track record guy. In the end you only have so many options and while you may prefer steak tartare, a dollar menu cheeseburger beats bread crumbs for someone who's starving. Best available option is secondary to best fit, but with Doc I think he's a coach that still will more often than not plays to his talent. That's what the Kings need.