😏 I need advice ......

Me and the kids dad have been separated for almost 6 years already .. our relationship was so toxic. Where he was abusive emotionally and physically.. 2 years ago, we had an argument where he pushed me back hard and I tore a ligament in my ankle.. my kids were there when that happened ... So like about 3 months ago he contacted me asking he misses the kids and wants to see them(mind you it's been almost 2 years where he hasn't asked to see them or talk to them since the incident ) ... I talked to the kids and they said they didn't wanna see him that they are not ready .. I told him how they felt . And now hes asking for me and him to have lunch and talk like grown adults .... I have a fiance that I've been with for 3 years now . And I havent told him anything.. just that he recently contacted me . And he said not to reply back .. but he doesnt know that I've been replying ... idk what to do ....... the kids dont wanna see him.. my family and fiance thinks it's a bad idea to even start having contact with him.. I just want the kids to have there father in there life .. even if it takes him long to get there trust back