You have basically three choices:
1.) Let him handle his own broken hand....after all it didn't happen at work.
2.) Make a bunch of phone calls and attempt to negotiate a better price here in the US.
3.) Take/send him to Mexico.
Also, remember that open enrollment in the health care marketplace starts in November.
Families that make less than ~$60k get a subsidy to help pay their premiums. Get your people to sign up, get what subsidies they can, then just pay them enough extra each month to cover the premiums.
The only catch: somehow you have to make sure they actually continue to pay the premiums (with the extra money you give them) to keep their coverage...so when something like this broken-hand-at-home arises, it's not a problem.
It could be possible that your company can pay their premiums directly, to insure they keep the insurance and don't just pocket the money...?