In some countries it's cash up front for surgery or medical treatment (China, India, Brazil, Africa), so be thankful he's in the USA. (During the 1930s in the USA maternity care was not a sure thing, and I heard stories of babies being held hostage for payment.)

Schedule appointment asap, it will only get worse without care. When they ask for insurance information, say none and make sure to ask if there is an out-of-pocket discount. There often is.

Paying cash is preferable to the hospital because insurance companies nickle and dime every bill and so providers have to overbill just to get paid their expected amounts. This leads to a normal "cash" discount, which even some "self-insured" companies take advantage of - so don't be shy. (Essentially without 3rd party insurance coverage, you are self-insured.)

Ask for an estimate of work from the doctor/surgeon and remember paying for the initial procedures is just the beginning, there will be follow up to make sure the bone is healing properly, antibiotics, etc. Avoid further injury if at all possible.

Typically hospitals here offer a payment plan, although being out of work even that seems a challenge. In your/his case, maybe paying $1000 up front, and then negotiate a payment plan for the rest. Hopefully he heals well, and gets some kind of income or family help in the meanwhile.