Learned this from Laura Phelps Sweatt -
Attach a band to the bottom of a power rack/floor attachment then to your dip belt, then walk in place.
Hanging weights off the belt doesn't really mimic the same traction motion you get from walking. Sure there's the downward force but there's no upward pull on the weights like you'd get on the belt machine.
Using a band will give you downward force and allow for an upward force.