I think maybe it is best to put him straight in his own bed rather than in your bed and then moving him. Maybe he wakes up as he is not where he expects to be (where he fell asleep) ifkwim.
I actually saw a program a few months ago about a girl with really bad sleep problems, and the solution was just to be very strict about her being in her own room and making it as boring as possible when her mum went in to see her, for example she had to just check on her, then not speak (or not speak much) as the stimulation of mum wasn't helping. Not sure if that is useful for you.