At that level the insurance contracts are individually negotiated so you can do what you want (at a price obviously). Also depends on the contract I guess, and any terms included around career-ending injury for example. If the player could see it terminated then he'd insure, if not then I'd...
Doesn’t sound that unrealistic - ballpark income protection cost say £10/month for £2,000/month at age 25 through to 65, so £5k/month would buy £1m/month cover at the same rate.