8 month old not sleeping

I for sure thought that by the time my son was 8 months old he would sleep thru the night. This isn't the case. He's always been a terrible sleeper and out of desperation we brought him into our bed to co sleep hoping that would help him. We started getting him to sleep in his crib for a few weeks - still waking up multiple times a night. Then he had another sleep regression and we brought him back into our bed. Now that the sleep regression is over we have moved his crib in his room and trying to get him to sleep in it again. Usually at point during the night (around 2am) he will wake up and refuses to go

Back to sleep in his crib. Last night I tried for an hour. I'll rock him and get him completely asleep, but once his head hits that mattress he starts crying again. I let him cry for about 5 minutes and then go in to console him. I did this for an hour and then gave up. I need advice please. I know I probably shouldn't have brought him into our bed at all but that was the only way he would sleep when he was younger. What should I do? Should I try the cry it out method? He's still eating between 2-4 bottles a night. And waking up between 2-5 times a night.

FYI - he has a comfortable memory foam topper so his crib is comfortable. We do a night time routine with pajamas and songs. The temperature is comfortable for him. White noise doesn't phase him at all. Bedtime is at 8:30 and wakes up at 7am for the day.