He probably doesn't see any point in bringing in an outsider and showing him the ropes when he'll likely be gone in a season or 2. Cummard is a bright young up and comer in the business who was coached by Rose for 4 years and then spent a couple of years as a grad assistant so he knows Rose as good as anyone and knows his system and what he wants out his players. It's not the sexiest hire that Rose could've made but I can see why he went with Cummard under the current circumstances.