Giving a registered sex offender a chance

I met this guy on bumble a couple months ago. I really like him and think he's great. But my mom is a nosey person and googles everyone I date or become friends with. I think part of it is because she's careful who she lets around my nephews. My brother died 5 years ago so my parents have guardianship of my nephews and I usually take them on weekends. They haven't met him yet but my mom told my he's a registered sex offender and screenshot it to me. He was charged with rape in the first degree on a minor and that the victim was between 5 and 14. I spoke to him about it and he told me when he was a teacher a former student said he raped him when he was 10(5th grade) and he came forward about it when he was 20 so 10 years later and took the plea deal to avoid jail time and that he didn't actually do anything. My dad's opinion on what he told me is if he was a teenager being interrogated for hours, or something with a disability or literally being tortured than he can believe he would admit to something he didn't do. He believes the guy came forward 10 years later so the chances of my boyfriend getting off were pretty high. He doesn't believe a grown man is gonna admit to raping a child when he didn't especially when his chances of getting off are high. My mom said if I continue this relationship my nephews can't come over anymore. And I love my nephews. Do you think I he's telling me the truth or a liar?