Cosleeping bedtime advice

Looking for advice from ladies who successfully cosleep (bedshare) with their babies. We introduced an in-bed bassinet to get my now 9 week old son to sleep, and it’s great. He sleeps wonderfully, wakes to eat, and goes right back to sleep until about 7am. The only trouble: we don’t want to share his bedtime 😂 I’ve started going to bed after his 9pm feed, but try as i might NOTHING will get this boy to sleep before then. We do lights off, quiet, walking with gentle lullaby, bathtime routine followed by breastfeeding and cuddles, even a nightlight with a specific lullaby starting at 630pm...nothing. 9pm or bust. I swear my kid is laughing at me 👀 so what do you ladies do? Do I need to start going to bed at 630/7?!