I don't know what to suggest either, but I did want to say I know the frustration of not having "proof". My exAH is so similar to everything you describe (except that our children are older which helps prevent your current problem). He also was the boss at work (just sold the business and works for larger company that bought them doing same thing) and makes a very good living. But at home,it started to become a nightmare. Same as you described and started getting mean and bossy,etc. It was our word over his;esp. when we went to a counselor. People think the kids I I "over-reacted" and exaggerated,etc (basically called the kids liars,etc which was sad when they told his dad and brother and sister). Since then we have gotten help and don't try to "convince" anyone,although it would have been nice when he took me to divorce court. It is frustrating and made me second-guess myself for a long,long time.
My exAH also would drive sometimes and never "looked" drunk but he had no business being on the road. He still does it and argues that he can drive perfectly well,etc. and the anger is as much a problem as the drinking (behind the wheel or not).
Hey, just remembered something; I just saw a devise on TV that the courts in California have that perhaps he could wear....ankle braclet that detects alcohol. A long-shot but maybe since he isn't supposed to drink when they are there,it is a possibility? Maybe worth checking into with the court/your attorney?
Good luck!