In matters such as this, don't be surprised if the contractor has nothing to do with the slow completion rate. I have no idea who the contractor is nor do I care but it could be that UL is not putting up the money or intentionally telling the contractor to delay completion because they are waiting on funds to clear, etc or for some other reason. It may be more convuluted than one thinks.
If it was just a matter of kicking the contractor's butt I personally believe that would have been done a long time ago. I smell a rat!!