where have you been going to trigger it? you gotta rest at your house at the time of 20:00 for 8 hours and he should show up then. if you're going to his place or your hut in the forest it won't trigger. if you're doing this entirely right then maybe some other requirement i can't come up with is incomplete or its a glitch, lets hope it's not a glitch as glitches are far more annoying.