Exercises that involve being up on your toes, i.e. Siff lunges (like a normal lunge but on your tip-toes), sled dragging up on toes, etc. Maybe also weighted jumps, olympic lifts. Can't guarantee they'll work but worth trying.
Other idea would be to try to alleviate the p-f issues with fascia release/ rolling on hard ball and/or strengthening the tibialis anterior with static holds and maybe some inventive cable work to add resistance to dorsi flexion?