Ambivalent feelings in social circles, what would you do?

My husband and I have been involved in two social circles for many years. One 9 yrs, the other almost 12, both somewhat intertwine with each other. Along the way we had made many friends (or so we thought) and had attained high status. The status was never an issue for me, but my husband enjoyed it. Anyway, back on Labor Day weekend, a major event happened. Quite a handful that signed up to help with a function did not come. Nor did they give any notice. Naturally that made this function very stressful for those who DID help. This made me very upset and hurt that our so called 'friends' weren't there for us as promised, instead having a pool party at home with most of the folks who also didn't show up as promised. A particular man who came to help at the function acted rather odd. He told MY volunteers who were previously told what time to arrive, an entirely different time (2hrs LATE). This was the 3rd time I was in charge of a function for which he deliberately tried to undermine in some way. Not only that, he also made sure that his personal cronies were in attendance while our 'friends' apparently weren't there. He made a sideline deal with someone else to 'give away' our supplies that attendees were supposed to purchase. For which he NEVER consulted me, as the chairperson in charge, or the membership of our club. I was simply 'INFORMED' after the deal was made, and the announcement over the speakers to the crowd. On a tight budget as it was, and our club there to SELL PRODUCT AND MAKE MONEY, this fell upon MY SHOULDERS to explain to 100 other members why we LOST income for product. Next, this man makes up lies about something my husband supposedly did at this event, and stooped so low as to get one of his crony's DAUGHTERS to give false statements. Then went on to make a public spectacle of it all AFTER calling secret meetings behind our backs. His allegations were never brought to our attention until EVERYONE in the uppermost echelon was given his and his cronies' version of the story and we were already prejudged in this matter. Of course this all spread like wildfire. We were undermined, blindsided, lied on, and persecuted quite unjustly. We never had a chance to defend ourselves. Motives were purely because WE knew damaging things about HIM, and even though we kept our mouths shut, only telling our District Leader, because he had already tried to start trouble when I was President the year before. I only divulged it in confidence to explain why we had issues with a bartender, and why he was on such a rampage about me. Because he was clearly out of line to A) smoke dope on the property B) with the bartender C)and propositioned her for sex... he was HER DIRECT SUPERVISOR. She called me that night, very late, and was crying. She owned up to smoking with him, but, felt cornered and feared losing her job for not complying with the sexual favors. Now knowing this, I also accidentally found out that he was downloading porn on the office computer. Again, I kept quiet to the masses, and only told my husband about it. He thought no big deal, and I was honestly appalled by this misuse of property. But, it made perfect sense why he would lock himself in there now and then, and why he'd step out of line with an EMPLOYEE. We made sure to be at the club every time it was open, just to keep an eye on things, basically for the bartender's peace of mind. Now that you know all that, back to the original issue...

So, when all of this went down, only my husband, myself, and our District Leader knew the details of what this guy was like.. or what he had done before. We have a code that we quietly handle things from within. Seems stupid to me now, because WE played by the rules, and he apparently doesn't, yet, he gets away with unjustly and publicly ruining OUR reputations? Nobody else knew what was going on behind the scenes, not even HIS wife and kids (they're the reason we didn't hang him out to dry). Blindly, EVERYONE took his side. My husband was asked to resign, and I voluntarily turned my resignation in the next day. Then I find out even more lies said about us, my husband was furious, I was livid. Now, here is my actual dilemma: The next President in line has begged me to come back and work with her, as her right hand. This awful man is still there, with all his smiles, charm, sneakiness and cronies. Although our 'friends' NOW know some of the true details about him, they don't know ALL of it, and the list is long. As my husband and I had decided as a couple to just step back and only be members, I find myself in a situation that is difficult. Our friends want us back, and our next President was ALWAYS there for us. With the few qualified people she has to work with, she honestly needs my help. I'm torn. I feel it will only be more conflict to deal with. So, what would YOU do if in my shoes?