Is this sexual harassment and what can/should I do?

I live in Canton, Ohio. So I've been working with my girlfriend for about a year. She's a dietary aid in a nursing home. I found out that there was an STNA that has constantly been hitting on her, making her uncomfortable, even after she told him she had a boyfriend. He would say things like "when are you going to break up with your boyfriend and move into my big house" or "He's so big and you're so tiny how does doing it work out". Mind that everything he does is on the clock and to multiple women. When I found out about this I was furious, so I waited until he and I were both of the clock and work property and called him. Originally I wanted to talk to him like a man but he said "say it to my face b*tch" and hung up. I flipped out and seeing red left him a message on his voice mail saying I would kick his teeth in and break his legs backwards. I know I shouldn't have done that but who wouldn't do that for their girl? Anyway the next day I called work and they told me they would talk to me when I got there. I get there and they have me write a report and tell me I'm suspended until the investigation was over. Within this time 5-8 other women filed reports against this guy. A week and a half goes by and never heard anything about my job. They finally called and told me I was fired. A few days later they let the guy who was in my opinion sexually harassing these women back. Some he physically contacted, arm around them, stuff like that. Their reason is because 2 of the 5-8 people couldn't be trusted. One was "offering themselves to him" and the other is just a liar. I don't feel it's right that they let him back let alone fired me. My girlfriend is in fear of working with him and doesn't think she should have to change her schedule for this creep. The entire reason I said something to him was because I knew this exact situation would happen. We're talking to a lawyer tomorrow but is there anything we should do? Do any of you feel like there's a legal case against him or the actual company we work for? I would think if anyone was labeled as a sexual predator they would be fired especially with other women supporting this. Thanks in advance.