Anything you can do with a KB can be (mostly) done with a DB.
Careful taking that KB OH. If you are off by just a little, you won't have been the first person who forcefully shoved the handle of it into your mouth (chin, neck).
In order for those step back pass through lunges to count for the Rx, a knee must touch the ground each time. Otherwise you are scaling. Which is cool. Unless you aren't.
Confused folk will often ask, "Should we be concerned with extending our hips at the top of a box jump?" Answer is: Sure! And also, I don't care! Fact is, short and long box jumps are each as hard as the other. The sweet spot occurs somewhere in the middle. We program for the sweet spot. Everybody's sweet spot is just a bit different. If someone wants to make them harder - fine! But remember, harder doesn't always = better.