Will this charge affect my husband getting a job?

This type of issue is usually considered a civil matter, had he not paid the amount when you recieved the court papers he would have likely been charged with criminal offence. As he did you have little to worry about the case may show up on the background check, but most any employer would shrug it off or just ask for a simple explanation. Being that he is applying to be a prison guard there is virtually no chance they would disqualify him based on this as they are desperate for more workers in the prison system.