I read something on the website about ID requirement along with vax cards to be admitted into the theatre.. is this true? Will I also need to bring an ID with my vax card? What if I don't have an ID right now?

They asked me for both when I was last there two weeks ago.

I was there last week and they do still request Vax cards. I'm not certain if they'll demand ID as well if you don't have it. I would recommend adding your vaccine record to your phone via Google Pay which combines Vax status and verified ID into one. Never been asked for separate ID with it yet.