Is there an employment lawyer in the house? Is this roughly correct?
Pro footballers are contractors, but in effect, employees as they are not free to work elsewhere and their employer dictates their working conditions etc. Their contracts, insurance and other things are covered under the Professional Footballer Association. By the way, I would expect the PFA to have a viewpoint on a young pro's 3 year contract being terminated after 12 months (If that is what has happened. I realise this is speculation, but in the light of no other information, that is what you get).
Amateur footballers (who can be paid petrol/boot/coaching/rent money) however are not covered by PFA and generally free to earn money anywhere/anyway they can - generally achievable as an amateur club is only demanding their presence in a part time capacity.