Angela, don't give up, you have Insurance bin the client I agree with what someone els said id tell him he's a muppet and hang up the phone he needs to expirience some good old fashioned window cleaning customer care ,
Now regarding you don't make enough money having 17 staff sounds like you're doing extreamly well I'm sure you don't employ to do people favours you have to be making substantial profits?! Why els would you have the stress of managing 17 people surely you are doing something right!and well done if so ,
regarding the claim even worse case scenario and This is all in the air if say insurance wouldnt pay it a sprained ankle injury surely can't be more then a couple of thousand im guessing your client will try and pass that on to you? it doesn't sound like that sort of amount will even impact a 17 staff strong turn over, I have no idea if your profit margins are extreamly low per man days and in which case then I can understand why you are worried,look good luck with it this sort of stuff is always bound to happen to anyone your size or even smaller so its important for others reading who are also employing to ensure right insurances are in place and procedures followed
Keep us update hope any financial claims are covered and sorted by your insurance regardless