Not really, accept that he definitely needs professional therapy from a licensed personal who is experienced dealing with that specific form of PTSD.
Remember, you aren’t his therapists, nor can you ever be, and trying to fill that role won’t be good for either person.
I had to learn this the hard way with a friend of mine who grew up with a very rough childhood. Lots of deep trauma, some pretty horrible stuff. I was trying to act like their therapist without intending it, and they started unintentionally treating me like a therapist.
It caused a lot of problems in our friendship and almost ended it actually. I had to eventually tell them, “I care about you, but I’m not your therapist, and I can’t ever be your therapist. You need professional help to deal with your trauma.”
Lots of space, no even hints of a relationship for a long time, (years). It takes a long time to heal from that level of trauma, and there isn’t anything wrong with that. If at the end of all that, he’s truly a new person, fully healed, and there is still a potential spark, then it’s a different situation.
But until then, And I do mean several years at least no relationship, trust me, you both will be better off.
PS, not sure if you’re also getting professional therapy, but if you can, do it. You very likely need it too, and I say that lovingly. I have received it myself and seen many people I know get helped by it.