What would you do in my situation?

About 6 months ago I broke up with my ex and moved on with someone new. We broke up for a number of reasons, he parties a lot.. I don't. He's interested in things I'm not. He just has a high risk lifestyle and I'm too motivated by my career that I can't make stupid risks like he does. We mutually agreed to break it off. Yet for some reason he still continued to try and sweet talk me into hooking up with him again even when I started dating someone else! He always made excuses for reasons why we needed to meet up, favors I could do for him that would eventually lead to him trying to put moves on me. Eventually I grew tired of it, told him to **** off and leave me alone. That I would not ruin my now awesome relationship with someone I have everything in common with for someone whose not serious about what he does. He backed off when I did that, but he still found ways to make sure we would run into each other. Now things get crazier.. my current boyfriend has an ex girlfriend who is into illegal business, she runs an immigration fraud business by marrying people into the country to get their citizenship and pays people to do it. I was someone she offered the money to but I declined. I know exactly what she does but I choose to stay as far from her as possible. Well, one day I guess my and and my boyfriends ex were partying together... and then police show up at a club that was robbed. they were both there, my ex is an undocumented immigrant, she accused him and now he was arrested and put in jail until he can see a judge. I have information that can get her in serious trouble and possibly drop the charges on him, but if I get involved it will ruin everything for me: My current relationship, possibly my new and awesome job with the state that gives me retirement benefits! I still care for this man as a friend and I dont want to see this ruin his life, I already visited him in jail once and feel sick to my stomach like I cheated on my boyfriend. But I went with his sister who begged me to go because he said he wanted to see me so bad. I don't understand why he still feels like he needs to see me when he is only allowed a certain amount of visits a week and why would he use one on me??? To make matters short because I know I'm typing an essay here... I just don't know what to do. I want to visit him again but I don't think I should. My current boyfriend is amazing and treats me right in every way, I feel I should tell him what's on my mind but I'm afraid he'll get mad at me or want to break up. He knows that my ex's sister called me and told me everything about whats going on and asked me to visit him because I told him, but I still feel weird about everything. Should I just forget about my friend/ex and let him deal with his **** on his own? Or should I provide support? I already decided not to get involved with the legal matters concerning the girl.. but this is just too complicated for me. If you were in my situation what would you do?? I know this guy and I know he didn't do what he was accused of, he may be an idiot but he just wouldn't steal from a club for sure. On top of all this, immigrations was called on him and he could be deported. :/