If a person is out of status for more than 180 days, that person would face a 3 year ban after exiting the US. A year or more out of status would accrue a 10 year ban after exiting. Yes, the normal route would be consular processing and a spousal visa if he leaves. Now that he has overstayed ESTA, it is revoked.
The best courses of action would be to find a qualified joint sponsor and file proper I-485, I-131, I-130, and I-765 packages asap.