Nothing against DJ, but I think keeping him would be a mistake. Holland needs to change the culture and put a stamp on how he wants the team to look by selecting his own HC rather than inheriting one.
Also what is the definition of insanity? At this point for the Kings it is to continue the cycle of promoting an assistance coach to the head coach role. It's time to break the cycle of ineptitude.
If they do keep DJ, it really needs to be on a 1 year "prove it" contract as I think DJ's coaching style will lose reception with the players more quickly than most (to his credit, though, he did get an extension after his first two years with Ottawa). This also gives an alternate option, such as Lord, and extra year in the AHL before attempting to make the jump.