Excellent advice Tracy - the social worker is the perfect person to help through the medicaid application process. If he qualifies, and they can tell you right away if he does or doesn't, then he will be considered "medicaid pending" and can stay in the nursing home on the pending status.
Because of his income - his contribution to cover a portion of his care in the nursing home will likely be large. You're in a tough spot here but the social worker can help you get through this!
Best of luck - hope you can figure this financial piece out so that you can focus on the really important stuff - family!