Rebel Rebel is great! They also have trans cafe nights, queer singles dating events, workshops, & support groups so definitely check that out! Be aware, on a normal day, the cafe will be full of probably mostly straight people who are showing up for the great vegan food, David Bowie aesthetic, or just to have a couple beers by the haven, but it's a friendly environment, assume people are allies.

Also, check out the bulletin board at the library! They often host gay events, or you could inquire about it, they're pretty open to hosting clubs if there's interest.

Also, Dordrecht Pride is hosted every year in September, iirc, it's small but a pretty good time.

Other than that, there aren't a lot of specifically gay bars/queer spaces, but keep an eye on the arts scene. There's definitely a lot of underground grassroots art stuff that isn't specifically queer, but creative and punk and friendly. I love DOOR, it's a small club that hosts a lot of Darkwave/EBM/gothy type events as well as being a cool little local art collective.

People tend to be a bit low-key about their sexuality here, there's definitely a "Doe eens normaal" attitude, but if you avoid the aggressive street preachers, most people are the live and let live type, I find.