Contact naps - no judgement please

My son was born at 37 weeks. He ended up in the NICU. He had a collapsed lung and was on a ventilator and came home healthy after 13 days in hospital. He was a normal birth weight 7lbs 6oz. Since we almost lost him, once I was able to hold him, I kind of never put him down (I know how bad it is). I slowly started getting him used to sleeping without being held. He was doing so well! Then the 4 months sleep regression came, and I can’t get him to settle alone. At night, he will sleep in his bassinet which is beside me. I rock him, and put him down when he is almost asleep, but let him fall completely asleep on the bassinet, usually holding my hand. I CANNOT for the life of me, get him to nap without being held. Not in his swing, not in a play pen, not in his crib. He maybe will do 20-30 minutes and then wakes up and can’t be settled back down unless I hold him. His naps are generally 1.5-2 hours ish. So not being able to do anything in that time is super frustrating. I get that I put myself in this situation, but I can’t see a way out if it. Any help is super appreciated, ideas I could try or just anything.