Do you do gait retraining? Have you thought about manipulating step rate to change foot strike? If not, you may want to check this out.
"The intent of our study was to determine whether step-rate manipulation alone was enough to change foot-strike pattern in shod recreational distance runners. We found increasing step rate above the runner’s preferred rate by 10% was successful in changing foot-strike pattern from a heel-strike to a midfoot- or forefoot-strike pattern in 17.5% of the runners, while increasing step rate by 15% changed foot strike pattern in 30%. These results suggest step-rate manipulation alone may be an effective way to change foot-strike pattern in a small percentage of shod distance runners."