Whatever issues Rey Mysterio had with WWE seem to longer exist as he seems happy with his current position. His knee is still bothering him but right now he isn’t planning to take any time off.
Stories going around about Rey’s contract expiring soon aren’t true as he has almost five years left on his deal. There is a clause in his contract that would allow him to retire as an in-ring competitor in less than five years, if his body isn’t up in good enough shape to continue. If that were to happen, WWE would retain his in-ring rights.