Plantar is a fucker. I had it for about 2 years, excessive running and cycling would cause it to erupt. Absolutely fine while exercising, but once you finish, it hits and doesn't stop. On bad days the pain would radiate through the heel, into the ankle and calf, and on a bad day, right up to the back of the knee. All of this subsequently affects other areas as you then have to adjust your gait.
I had physio, which involved a lot of stretching for the calf's, and some shoe inserts which were over £300. All this helped. However, while it was improving, I tore my meniscus when doing leg day in the gym. I have since had the knee surgery - a little over 4 weeks ago. So, the plantar is better but might because of how little I am doing of late. The physio mentioned shockwave therapy as a solution if it doesn't heal.
If this is Stones' issues, I hope he can get over it. He'll have the best advice and facilities available. It can be fixed.
He's a brilliant footballer, and badly missed right now.