Oh Cumbria, how exhausting - I wish I had an answer :( I will write my experience
Why is he terrified ? I feel like this is one that need gradual work, creating a positive experience of sleeping, with perhaps a musical cot mobile, a low sleeping light, some story telling or singing, some hand holding, etc ? I know you want this to end now though ...
We do all those things and that etc for us still is a dummy, he still looks forward to have his dummy in bed, he can only have it in bed
Even though we do things to make going to bed like a little nice experience recently he prefers to be awake and refuses to get ready for bed, but he also get it that he has no other choice , he knows we will put him in bed anyhow, so by the time he is brushing his teeth he knows the battle is lost and takes it easy afterwards
But we still spend lots of time with him before bed, far too much for a tired parent after work, I think he is not ready for us to cut that time though
One of us stays with him next to his bed until he is asleep, most nights he also asks to hold hands, many nights he has his own little individual request for a story or a song , he tells us specifically what he wants ; he still has his little cot mobile which we take with us to any trip, and this cot mobile has a very low light too ; the music of the cot mobile means it is sleepy time now
Next thing I need to do is to add gro clock because some nights he wakes in the middle of the night and has to b told it is middle of the night and he has to go back to sleep and he is not Very pleased about that then